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%I #8 Jun 29 2018 03:58:05
%S 1,4,9,10,11,14,19,22,28,33,40,41,44,49,55,66,77,82,88,90,91,94,99,
%T 100,101,104,109,110,111,114,119,122,128,133,140,141,144,149,155,166,
%U 177,182,188,190,191,194,199,202,208,212,218,220,221,224,229,236,242,248
%N Numbers the product of whose nonzero digits is a perfect square.
%H Harry J. Smith, <a href="/A062371/b062371.txt">Table of n, a(n) for n = 0..1000</a>
%e 128 is a member as 1*2*8 = 16 is a square. 140 is also a member as 1*4 = 4.
%o (PARI) ProdNzD(x)= { p=1; while (x>9, d=x-10*(x\10); if (d, p*=d); x\=10); return(p*x) } { n=-1; for (m=1, 10^9, if (issquare(ProdNzD(m)), write("b062371.txt", n++, " ", m); if (n==1000, break)) ) } \\ _Harry J. Smith_, Aug 06 2009
%K nonn,base,easy
%O 0,2
%A _Amarnath Murthy_, Jun 26 2001
%E Corrected and extended by Larry Reeves (larryr(AT)acm.org), Jul 06 2001
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