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 A061869 Squares whose sum of digits as well as product of digits is a square (allowing zero). 2

%I #15 Feb 16 2023 05:40:09

%S 0,1,4,9,100,144,400,441,900,2025,2304,2601,3600,8100,9025,10000,

%T 10201,10404,10609,10816,11025,12100,14400,14884,16900,19600,21904,

%U 22500,30625,30976,32400,40000,40401,40804,41209,44100,44944,48400,48841

%N Squares whose sum of digits as well as product of digits is a square (allowing zero).

%H Robert Israel, <a href="/A061869/b061869.txt">Table of n, a(n) for n = 1..10000</a>

%p filter:= proc(t) local L;

%p L:= convert(t,base,10);

%p issqr(convert(L,`+`)) and issqr(convert(L,`*`))

%p end proc:

%p select(filter, [seq(i^2,i=0..300)]); # _Robert Israel_, Feb 15 2023

%t spdQ[n_]:=Module[{idn=IntegerDigits[n]},IntegerQ[Sqrt[Total[idn]]] && IntegerQ[ Sqrt[Times@@idn]]]; Select[Range[300]^2,spdQ] (* _Harvey P. Dale_, Jan 24 2013 *)

%Y A061267 does not allow zero products.

%Y Subsequence of A061867.

%K base,nonn

%O 1,3

%A Larry Reeves (larryr(AT)acm.org), May 11 2001

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Last modified May 28 00:06 EDT 2024. Contains 372900 sequences. (Running on oeis4.)