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%I #22 Jul 17 2021 04:29:33
%S 1,13,41,61,125,212,281,613,1156,1424,2225,3232,3316,4113,11125,11281,
%T 11525,12816,14913,16317,16441,19125,21284,21625,24128,25216,27521,
%U 31525,53125,56116,61321,65161,71325,82116,82217,83521,84313,111812,113125,113625,115336,115681,117125,118372
%N Numbers m such that m = p^2 + k^2, with p > 0, where p = A007954(m) = the product of digits of m.
%H Giovanni Resta, <a href="/A334557/b334557.txt">Table of n, a(n) for n = 1..10000</a>
%e 13 is a term as p = 1*3 = 3 and 13 = 3^2 + 2^2.
%e 281 is a term as p = 2*8*1 = 16 and 281 = 16^2 + 5^2.
%e 118372 is a term as p = 1*1*8*3*7*2 = 336 and 118372 = 336^2 + 74^2.
%o (PARI) isok(m) = my(p=vecprod(digits(m))); p && issquare(m - p^2); \\ _Michel Marcus_, May 06 2020
%Y Cf. A007954, A000404, A078134, A334542, A334558.
%K nonn,base
%O 1,2
%A _Scott R. Shannon_, May 06 2020