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A073613 Triangular numbers which are the sum of two nonnegative squares. 1
1, 10, 36, 45, 136, 153, 325, 666, 820, 1225, 1378, 2080, 2628, 2701, 3240, 3321, 4005, 4753, 5050, 6786, 7381, 9316, 10440, 10585, 11026, 14365, 16290, 18721, 19306, 25425, 27028, 27261, 29161, 29890, 32896, 33930, 41616, 41905, 42778 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..39.

MATHEMATICA

t = Range[0, 250]^2; t1 = Flatten[Table[a + b, {a, t}, {b, t}]]; t2 = Accumulate[Range[300]]; Intersection[t1, t2] (* Jayanta Basu, Jul 03 2013 *)

Select[Union[Total/@Tuples[Range[0, 300]^2, 2]], OddQ[Sqrt[8#+1]]&] (* Harvey P. Dale, Apr 22 2015 *)

CROSSREFS

Intersection of A000217 and A001481.

Sequence in context: A125550 A223305 A176575 * A117404 A072517 A271912

Adjacent sequences:  A073610 A073611 A073612 * A073614 A073615 A073616

KEYWORD

easy,nonn

AUTHOR

Jason Earls (zevi_35711(AT)yahoo.com), Aug 29 2002

STATUS

approved

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Last modified July 21 02:56 EDT 2017. Contains 289629 sequences.