A267297 - OEIS

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A267297

Square triangular numbers that are the sum of 2 nonzero nonconsecutive triangular numbers.

1225, 41616, 1413721, 1631432881, 55420693056, 1882672131025, 63955431761796, 2172602007770041, 73804512832419600, 2507180834294496361, 85170343853180456676, 2893284510173841030625, 98286503002057414584576, 3338847817559778254844961, 113422539294030403250144100

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OFFSET

1,1

COMMENTS

Subsequence of A001110. Conjecture: except for the terms 0, 1, 36, 48024900, the sequence is identical to A001110.

LINKS

Chai Wah Wu, Table of n, a(n) for n = 1..50

FORMULA

Conjectures from Colin Barker, Mar 03 2016: (Start)

a(n) = 35*a(n-1)-35*a(n-2)+a(n-3) for n>6.

G.f.: x*(1225-1259*x+36*x^2+1583407981*x^3-1630019160*x^4+46611179*x^5) / ((1-x)*(1-34*x+x^2)).

(End)