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A356167
Greatest common divisor of A003961(n) and the smallest positive k such that n divides k*A003961(k), where A003961 is fully multiplicative with a(p) = nextprime(p).
4
1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 5, 1, 1, 1, 1, 1, 1, 1, 1, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 1, 5, 1, 1, 1, 1, 1, 1, 1, 3, 1, 1, 1, 1, 7, 1, 1, 1, 1, 3, 1, 1, 5, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 1, 1, 1, 5, 1, 1, 1, 1, 1, 3, 11, 1, 1, 1, 1, 1, 1, 1, 1, 9, 1, 1, 1, 1, 5
OFFSET
1,10
FORMULA
a(n) = gcd(A003961(n), A356164(n)).
PROG
(PARI)
A003961(n) = { my(f = factor(n)); for(i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); };
A356167(n) = for(k=1, oo, if((k*A003961(k))%n==0, return(gcd(A003961(n), k))));
CROSSREFS
KEYWORD
nonn,look
AUTHOR
Antti Karttunen, Jul 28 2022
STATUS
approved