A332984 Triangular numbers also sum of two nonzero pentagonal numbers.

6, 10, 36, 105, 528, 595, 861, 903, 1081, 1128, 1225, 1431, 1711, 2016, 2211, 2278, 2415, 2556, 2926, 3160, 3403, 3741, 4005, 4095, 5050, 5151, 5253, 6105, 6441, 6903, 7750, 8385, 10011, 11476, 12720, 14196, 15400, 15931, 16836, 17391, 18528, 19110

Offset

1,1

Links

Peter Kagey, Table of n, a(n) for n = 1..1000

Example

    6 =  1 +  5;
   10 =  5 +  5;
   36 =  1 + 35;
  105 = 35 + 70.

Crossrefs

A subset of A000217 (triangular numbers) and of A332987 (sums of two nonzero pentagonal numbers).

Cf. A000326 (pentagonal numbers).

Sequence in context: A068889 A203485 A221519 * A038264 A094890 A213477

Adjacent sequences: A332981 A332982 A332983 * A332985 A332986 A332987

Keyword

nonn,easy

Author

Olivier Gérard, Mar 05 2020

Status

approved