A264118 Numbers that can be represented as S1+S2, as T1+T2, and as S3+T3, where S1, S2, S3 are positive squares, and T1, T2, T3 are positive triangular numbers.
2, 25, 29, 37, 61, 65, 72, 100, 101, 106, 130, 136, 137, 157, 169, 200, 202, 205, 226, 232, 234, 241, 274, 277, 289, 340, 353, 389, 400, 409, 416, 421, 436, 442, 445, 466, 490, 514, 520, 522, 562, 577, 596, 610, 625, 637, 640, 661, 666, 676, 697, 724, 757, 765, 785, 794, 820
Offset: 1
Keywords
Examples
a(1) = 2 = 1+1. 25 is a term because 25 = 16 + 9 = 10 + 15 = 4 + 21, and 16, 9, 4 are squares, 10, 15, 21 are triangular numbers.
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