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%I #16 Mar 07 2022 07:57:35
%S 1,4,9,6,10,18,36,24,8,1,2,16,54,54,20,60,144,24,18,4,16,128,90,210,
%T 60,252,126,224,32,9,54,8,72,30,20,108,162,64,10,6,48,168,288,162,20,
%U 12,36,24,8,10,12,56,144,108,30,54,216,216,96,18,42,384,1458
%N Product of the nonzero digits (in base 10) of n^2.
%F a(n) = A051801(n^2). - _Michel Marcus_, Mar 07 2022
%e a(32) = 8 because 32*32 = 1024 and 1*2*4 = 8.
%t Table[Times@@(IntegerDigits[n^2]/.(0->1)),{n,120}] (* _Harvey P. Dale_, Dec 12 2017 *)
%o (PARI) a(n) = {digs = digits(n^2); prod(i=1, #digs, if (digs[i], digs[i], 1));} \\ _Michel Marcus_, Aug 12 2013
%o (PARI) a(n) = vecprod(select(x->(x>1), digits(n^2))); \\ _Michel Marcus_, Mar 07 2022
%Y Similar to A053667, which does not exclude zero digits from the product.
%Y Related to A218013.
%Y Cf. A000290, A051801.
%K nonn,base
%O 1,2
%A _Nels Olson_, Oct 19 2012
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