A002292 Related to representation as sums of squares.

1, 20, 74, 24, 157, 124, 478, 1480, 1198, 3044, 480, 184, 2351, 1720, 3282, 5728, 2480, 1776, 10326, 9560, 8886, 9188, 11618, 23664, 16231, 23960, 11686, 9176, 60880, 16876, 18482, 3768, 35372, 15532, 3680, 31960, 4886, 47020, 2976, 44560

Offset: 0

Author

N. J. A. Sloane

Keywords

• nonn

Comments

This is A225923 without the minus signs. - Michael Somos, Aug 09 2018

References

• J. W. L. Glaisher, On the representation of a number as sum of 2,4,6,8... squares, Quart. J. Math. 38 (1907), 1-62 (see p. 56).
• N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
• N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Links

• Masao Koike, Modular forms on non-compact arithmetic triangle groups, Unpublished manuscript [Extensively annotated with OEIS A-numbers by N. J. A. Sloane, Feb 14 2021. I wrote 2005 on the first page but the internal evidence suggests 1997.]

Crossrefs

Cf. A225923.

Formula

a(n) = abs(A225923(n)). - Michael Somos, Aug 09 2018