OFFSET
1,3
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
EXAMPLE
24531 is in the sequence because (1) it is a hexagonal number and (2) the product of its digits 2*4*5*3*1 = 120 is also a hexagonal number.
MATHEMATICA
pod[n_] := Times @@ IntegerDigits[n]; hexQ[n_] := n == 0 || IntegerQ[(Sqrt[32*n + 4] + 2)/8]; Select[Table[n*(2*n - 1), {n, 0, 120}], hexQ[pod[#]] &] (* Amiram Eldar, Feb 06 2021 *)
Module[{nn=100, hx}, hx=PolygonalNumber[6, Range[0, nn]]; Select[hx, MemberQ[ hx, Times@@ IntegerDigits[ #]]&]] (* Harvey P. Dale, Aug 24 2022 *)
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Luc Stevens (lms022(AT)yahoo.com), Apr 16 2006
EXTENSIONS
Offset corrected by Amiram Eldar, Feb 06 2021
STATUS
approved