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%I #20 Feb 03 2017 15:35:31
%S 1,4,4,16,4,36,4,64,16,36,4,144,4,36,36,256,4,144,4,144,36,36,4,576,
%T 16,36,64,144,4,900,4,1024,36,36,36,1296,4,36,36,576,4,900,4,144,144,
%U 36,4,2304,16,144,36,144,4,576,36,576,36,36,4,3600,4,36,144,4096,36,900,4,144,36,900,4,5184,4,36,144,144,36,900,4,2304,256,36,4,3600,36,36,36
%N Least number with the prime signature of n^2; square of the least number with the prime signature of n.
%H Antti Karttunen, <a href="/A278254/b278254.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = A046523(n^2) = A046523(n)^2.
%F a(n) = A278259(2*n).
%t Table[Times @@ MapIndexed[(Prime@ First@ #2)^#1 &, #] &@ If[Length@ # == 1 && #[[1, 1]] == 1, {0}, Reverse@ Sort@ #[[All, -1]]] &@ FactorInteger[ n^2], {n, 120}] (* _Michael De Vlieger_, Nov 21 2016 *)
%o (Scheme)
%o (define (A278254 n) (A000290 (A046523 n)))
%o (define (A278254 n) (A046523 (A000290 n)))
%o (PARI) a(n)=my(f=vecsort(factor(n)[, 2], , 4), p); prod(i=1, #f, (p=nextprime(p+1))^f[i])^2 \\ _Charles R Greathouse IV_, Feb 03 2017
%Y Bisection of A278259.
%Y Cf. A000290, A046523, A278238, A278253, A278160, A278162.
%K nonn
%O 1,2
%A _Antti Karttunen_, Nov 19 2016
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