A132229 - OEIS

A132229

The set N such that each positive integer can be written in the form s^2 + n, s>=0, n in N, in an odd number of ways.

2, 5, 6, 8, 13, 14, 15, 16, 18, 19, 20, 21, 22, 27, 28, 31, 35, 36, 39, 40, 45, 46, 49, 53, 54, 59, 60, 63, 64, 65, 66, 67, 68, 69, 70, 72, 79, 80, 83, 84, 85, 86, 89, 90, 97, 101, 102, 107, 108, 113, 114, 117, 118, 119, 120, 127, 137, 138, 149, 150, 153

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

REFERENCES

Computed by Sam Taylor.

LINKS

Table of n, a(n) for n=1..61.

J. N. Cooper, D. Eichhorn and K. O'Bryant, Reciprocals of binary power series

FORMULA

The terms are the exponents in the expansion of 1/((1-x)S) read mod 2 where S = Sum_{s >= 0} x^{s^2}.

MATHEMATICA

m = maxExponent = 13;