A117985 Pentagonal numbers with only odd digits.

1, 5, 35, 51, 117, 715, 1335, 1717, 3151, 3577, 5551, 5735, 7315, 7957, 15555, 55777, 71177, 73151, 99717, 135751, 171197, 319935, 331115, 335357, 371757, 377755, 711737, 755795, 935755, 1111551, 1517551, 1553977, 1739355, 1911397, 1993537, 3131315, 3311551

Offset

1,2

Links

Harvey P. Dale, Table of n, a(n) for n = 1..1000

Mathematica

Select[Table[n*(3*n - 1)/2, {n, 0, 3000}], AllTrue[IntegerDigits[#], OddQ] &] (* Amiram Eldar, Feb 06 2021 *)
Select[PolygonalNumber[5, Range[1500]], AllTrue[IntegerDigits[#], OddQ]&] (* Harvey P. Dale, Oct 17 2021 *)

Crossrefs

Intersection of A000326 and A014261.

Cf. A117990.

Sequence in context: A128044 A299529 A014632 * A371561 A115707 A117793

Adjacent sequences: A117982 A117983 A117984 * A117986 A117987 A117988

Keyword

base,nonn

Author

Luc Stevens (lms022(AT)yahoo.com), May 03 2006

Extensions

Missing terms inserted by Amiram Eldar, Feb 06 2021

Status

approved