OFFSET
1,2
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..457
MATHEMATICA
aQ[n_] := (p = Times @@ IntegerDigits[n]) > 0 && IntegerQ @ Sqrt[8p + 1]; t[n_] := n(n+1)/2; Select[t[Range[10^3]], aQ] (* Amiram Eldar, Aug 12 2019 *)
Select[Accumulate[Range[1500]], FreeQ[IntegerDigits[#], 0]&&OddQ[Sqrt[8 Times@@IntegerDigits[ #]+1]]&] (* Harvey P. Dale, May 01 2023 *)
PROG
(Magma) [m:m in [1..600000]|not 0 in Intseq(m) and IsSquare(8*m+1) and IsSquare(8*(&*Intseq(m))+1)]; // Marius A. Burtea, Aug 12 2019
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Amarnath Murthy, Apr 05 2002
EXTENSIONS
More terms from Jason Earls and Lior Manor May 15 2002
STATUS
approved