|
%I #5 Jul 13 2021 19:41:57
%S 3,8,13,18,24,31,35,38,42,46,53,57,64,68,75,79,81,83,86,97,113,118,
%T 124,131,135,138,142,146,153,157,164,168,175,179,181,183,186,197,214,
%U 222,226,234,238,241,243,246,258,262,264,283,285
%N Product of digits + 1 is a square greater than 1.
%C Sequence is infinite.
%e 135 belongs to this sequence as 1*3*5 + 1 = 16 is a square.
%t pdsQ[n_]:=FreeQ[IntegerDigits[n],0]&&IntegerQ[ Sqrt[ 1+Times@@ IntegerDigits[ n]]]; Select[Range[300],pdsQ] (* _Harvey P. Dale_, Jul 13 2021 *)
%Y Cf. A081990.
%K base,easy,nonn
%O 0,1
%A _Amarnath Murthy_, Apr 04 2003
%E Corrected and extended by Antonio G. Astudillo (afg_astudillo(AT)lycos.com), Apr 06 2003
%E Definition (Name) clarified by _Harvey P. Dale_, Jul 13 2021
|
