A094973 Square numbers which equal a triangular number times an odd number between 1 and 15.

1, 9, 36, 196, 225, 324, 900, 1225, 4225, 11025, 41616, 53361, 88209, 108900, 176400, 324900, 374544, 1413721, 8643600, 12723489, 43956900, 48024900, 52490025, 158407396, 432224100, 468506025, 846984609, 1631432881

Offset

1,2

Links

Table of n, a(n) for n=1..28.

Valladolid problem set archive, Semi-triangular and also square

Mathematica

Select[Union[Flatten[# Range[1, 15, 2]&/@Accumulate[Range[60000]]]], IntegerQ[Sqrt[#]]&] (* Harvey P. Dale, Nov 02 2011 *)

Crossrefs

Cf. A000217, A000290.

Sequence in context: A264359 A280353 A110752 * A038780 A073984 A036907

Adjacent sequences: A094970 A094971 A094972 * A094974 A094975 A094976

Keyword

nonn

Author

Rahman Md. Miaznur (m_rahmanjewel(AT)yahoo.com), Aug 26 2004

Extensions

Edited by Don Reble, Mar 17 2007

Status

approved