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A331290
a(n) = gcd(A001222(n), A329348(n)).
4
1, 1, 1, 2, 1, 2, 1, 1, 1, 2, 1, 1, 1, 2, 2, 2, 1, 1, 1, 1, 2, 2, 1, 1, 2, 2, 1, 1, 1, 1, 1, 1, 2, 2, 2, 4, 1, 2, 2, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, 1, 1, 2, 2, 4, 2, 2, 1, 1, 1, 2, 3, 2, 1, 3, 1, 1, 2, 1, 1, 1, 1, 2, 1, 1, 2, 3, 1, 1, 1, 2, 1, 2, 1, 2, 2, 4, 1, 2, 2, 1, 2, 2, 1, 2, 1, 1, 1, 1, 1, 3, 1, 4, 1
OFFSET
1,4
COMMENTS
Records occur at n = 1, 4, 36, 112, 352, 1088, 2016, 2688, 8064, 63360, ...
FORMULA
a(n) = gcd(A001222(n), A329348(n)) = gcd(A001222(n), A331188(n) mod A117366(n)).
a(n) = gcd(A001222(n), A331289(n)).
PROG
(PARI)
A002110(n) = prod(i=1, n, prime(i));
A331290(n) = if(1==n, 1, my(f=factor(n), p=nextprime(1+vecmax(f[, 1]))); gcd((prod(i=1, #f~, A002110(primepi(f[i, 1]))^(f[i, 2]-(#f~==i)))%p), bigomega(n)));
CROSSREFS
KEYWORD
nonn,less
AUTHOR
Antti Karttunen, Jan 15 2020
STATUS
approved