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%I #18 Jun 20 2021 00:15:35
%S 10,20,145,178,183,203,802,1131,1202,1618,2436,2454,2810,2867,3218,
%T 3983,4645,4758,4939,5602,6989,7569,8166,8874,9023,9298,9407,9691,
%U 9821,10562,10845,12205,13138,14907,16739,16805,18482,19443,19858,19894,21445,26941
%N Numbers whose concatenation of prime factors (with multiplicity) is a square.
%H Sean A. Irvine, <a href="/A038693/b038693.txt">Table of n, a(n) for n = 1..1000</a>
%e 802 = 2*401 and 2401 = 49^2.
%e 1131 = 3*13*29 and 31329 = 177^2.
%o (PARI) f(n)={ n<4 & return(n); for(i=1, #n=factor(n)~, n[1, i]=concat(vector(n[2, i], j, Str(n[1, i])))); eval(concat(n[1, ]));} \\ A037276
%o isok(n) = (n>1) && issquare(f(n)); \\ _Michel Marcus_, Jan 28 2021
%Y Cf. A037276.
%K nonn,base
%O 1,1
%A _Jeff Burch_
%E Missing terms inserted and terms sorted by _Sean A. Irvine_, Jan 27 2021
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