Cite this article as:

Sherstyukov V. B. The problem of Leont'ev on entire functions of completely regular growth . Izv. Saratov Univ. (N. S.), Ser. Math. Mech. Inform., 2013, vol. 13, iss. 2, pp. 30-35. DOI: https://doi.org/10.18500/1816-9791-2013-13-2-1-30-35


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Russian
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The problem of Leont'ev on entire functions of completely regular growth

Abstract: 

We consider an entire function of exponential type with all its zeros are simple and form a sequence with the index condensation zero. On the set of zeros a function of its derivative is growing quickly. Required to determine whether original function have complete regularity of growth. This problem, which arose in the theory of representation of analytic functions by exponential series was posed by A. F. Leontiev more than forty years ago and has not yet been solved. In this paper we show that the aforesaid problem a positive solution if the function is “not too small” on a straight line. 

References

1. Leont’ev A. F. On conditions of expandibility of

analytic functions in Dirichlet series. Math. of the USSR-

Izvestiya, 1972, vol. 6, no. 6, pp. 1265–1277. DOI:

10.1070/IM 1972v006n06ABEH001918.

2. Levin B. Ja. Distributions of zeros of entire functions.

RI, Providence, Amer. Math. Soc., 1964. [Rus. ed.:

Levin B. Ja. Raspredelenie kornei tselykh funktsii.

Moscow, Gostekhizdat, 1956. 632 p.]

3. Leont’ev A. F. Riady eksponent [Exponential series].

Moscow, Nauka, 536 p. (in Russian).

4. Leont’ev A. F. Tselye funktsii. Riady eksponent [Entire

functions. Exponential series]. Moscow, Nauka, 1983,

175 p. (in Russian).

5. Korobeinik Yu. F. Representing systems. Russian

Math. Surv., 1981, vol. 36, no. 1, pp. 75–137. DOI:

10.1070/RM1981v036n01ABEH002542.

6. Abanin A. V. Slabo dostatochnye mnozhestva i abso-

liutno predstavliaiushchie sistemy. Diss. dokt. fiz.-mat.

nauk [Weakly sufficient sets and absolutely representing

systems. Dr. phys. and math. sci. diss.]. Rostov on Don,

1995, 268 p.

7. Bratishchev A. V. A type of lower estimate for entire

functions of finite order, and some applications. Math. of

the USSR-Izvestiya, 1985, vol. 24, no. 3, pp. 415–438.

DOI: 10.1070/IM1985v024n03ABEH001243.

8. Korobeinik Yu. F. Maksimal’nye i °-dostatochnye

mnozhestva. Prilozheniia k tselym funktsiiam. II [The

maximal and °-sufficient sets. Applications to entire

functions]. Teoriia funktsii, funktsional’nyi analiz i

ikh prilozheniia. Kharkov, 1991, vol. 55, pp. 23–34 (in

Russian).

9. Sherstyukov V. B. On a question about °-sufficient

sets. Siberian Math. J., 2000, vol. 41, no. 4, pp. 778–

784. DOI: 10.1007/BF02679704.

10. Sherstyukov V. B. On a problem of Leont’ev

and representing systems of exponentials. Math.

Notes, 2003, vol. 73, no. 2, pp. 286–298. DOI:

10.1023/A:1025068527611.

11. Sherstyukov V. B. Ob odnom podklasse

tselykh funktsii vpolne reguliarnogo rosta [On a

subclass of entire functions of completely regular

growth]. Kompleksnyi analiz. Teoriia operatorov.

Matematicheskoe modelirovanie. Vladikavkaz, Publ.

VNTs RAN, 2006, pp. 131–138 (in Russian).

12. Sherstyukov V. B. On some criteria for completely

regular growth of entire functions of exponential type.

Math. Notes, 2006, vol. 80, no. 1, pp. 114–126. DOI:

10.1007/s11006-006-0115-6.

13. Bratishchev A. V. On a problem of A. F. Leont’ev. Sov.

Math. Dokl. 1983, vol. 27, pp. 572–574 (in Russian).

14. Mel’nik Yu. I. O predstavlenii reguliarnykh funktsii

riadami tipa riadov Dirikhle [On the representation of

regular functions by Dirichlet type series]. Issledovanie

po teorii priblizhenii funktsii i ikh prilozheniia, Kiev,

Naukova Dumka, 1978, pp. 132–141 (in Russian).

15. Mel’nik Yu. I. Ob usloviiakh skhodimosti riadov

Dirikhle, predstavliaiushchikh reguliarnye funktsii

[Conditions for the convergence of Dirichlet series that

represent regular functions]. Matematicheskii analiz

i teoriia veroiatnostei, Kiev, Naukova Dumka, 1978,

pp. 120–123 (in Russian).

16. Mel’nik Yu. I. Ob usloviiakh razlozhimosti

reguliarnykh funktsii v riady eksponent [On conditions of

expandibility of regular functions in exponential series].

Vsesoiuz. simpozium po teorii approksimatsii funktsii v

kompleksnoi oblasti, Ufa, 1980, pp. 94 (in Russian).

17. Bratishchev A. V. Bazisy Kete, tselye funktsii i ikh

prilozheniia. Diss. dokt. fiz.-mat. nauk [Kothe bases,

entire functions and their applications. Dr. phys. and

math. sci. diss.]. Rostov on Don, 1997, 248 p.

18. Ingham A. E. A note on Fourier transforms. J. London

Math. Soc., 1934, vol. 9, pp. 29–32.

19. Levinson N. Gap and density theorems. New York,

Amer. Math. Soc., 1940, 246 p.

20. Sedletskii A. M. Klassy analiticheskikh preobrazo-

vanii Fur’e i eksponentsial’nye approksimatsii [Classes

of analytic Fourier transforms and exponential

approximations]. Moscow, Fizmatlit, 2005, 503 p. (in

Russian).

21. Levin B. Ja. Pochti periodicheskie funktsii s ogranichennym

spektrom [Almost periodic functions with

bounded spectrum]. Aktual’nye voprosy matematiches-

kogo analiza, Rostov on Don, 1978, pp. 112–124 (in

Russian).

 

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