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Least number with the prime signature of the n-th centered square number (A001844(n)).
2

%I #6 Nov 22 2016 21:49:23

%S 1,2,2,4,2,2,6,2,6,2,6,6,2,6,2,6,6,2,6,2,4,12,2,30,2,2,6,6,24,2,2,6,2,

%T 6,2,2,30,6,6,2,6,30,2,6,6,6,12,2,6,12,2,6,6,12,6,6,6,6,12,6,2,30,6,6,

%U 6,2,30,6,6,2,2,12,2,6,6,6,6,6,60,2,6,6,2,6,2,2,30,2,30,6,2,30,6,30,6,30,24,2,6,2,2,30,2,12,2,6,30,6,30,2,2,6,6,6,6

%N Least number with the prime signature of the n-th centered square number (A001844(n)).

%H Antti Karttunen, <a href="/A278244/b278244.txt">Table of n, a(n) for n = 0..10000</a>

%F a(n) = A046523(A001844(n)).

%o (PARI)

%o A046523(n) = my(f=vecsort(factor(n)[, 2], , 4), p); prod(i=1, #f, (p=nextprime(p+1))^f[i]) \\ From _Charles R Greathouse IV_, Aug 17 2011

%o A001844(n) = 2*((n^2) + n) + 1;

%o A278244(n) = A046523(A001844(n));

%o for(n=0, 10000, write("b278244.txt", n, " ", A278244(n)));

%o (Scheme) (define (A278244 n) (A046523 (A001844 n)))

%Y Cf. A001844, A046523.

%Y Cf. also A278162, A278254, A278259.

%K nonn

%O 0,2

%A _Antti Karttunen_, Nov 22 2016