

A110879


Let a_0 = 1 and for n > 0, let a_n be the smallest positive integer not already in the sequence such that (a_0 + a_1 x + a2x^2 + ....)^(1/3) has integer coefficients. (Hanna's A083349). Let f(n) = n th term in the present sequence. Then a_0 + a_1 x + a_2 x^2 + ... = (1x)^f(1) (1x^2)^f(2) (1x^3)^f(3) ....


0



1, 2, 3, 5, 1, 3, 3, 7, 6, 7, 23, 15, 12, 28, 48, 25, 10, 165, 4, 274, 408, 927, 932, 1179, 3745, 2906, 7620, 1471, 21283, 1593, 40509, 18877, 93870, 53839, 153551, 204285, 293171, 462306, 307359, 1227141, 282147, 2368041, 1025023, 5041701, 4100247, 7457707, 15096708
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OFFSET

1,2


COMMENTS

The preprint reference asks for a generating function for Hanna's sequence. Terms of present sequence are the exponents in an infinite product for Hanna's sequence. They were obtained from terms of Hanna's sequence with the cited theorem in Apostol and Mobius inversion.


REFERENCES

Apostol, T., Introduction to Analytic Number Theory, SpringerVerlag 1976, Theorem 14.8, p. 323.


LINKS

Table of n, a(n) for n=1..47.
N. Heninger, E. M. Rains and N. J. A. Sloane, On the Integrality of nth Roots of Generating Functions, J. Combinatorial Theory, Series A, 113 (2006), 17321745.


CROSSREFS

Cf. A083349.
Sequence in context: A256888 A010585 A295302 * A016587 A123217 A039704
Adjacent sequences: A110876 A110877 A110878 * A110880 A110881 A110882


KEYWORD

sign


AUTHOR

Barry Brent (barrybrent(AT)member.ams.org), Sep 19 2005


STATUS

approved



