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A351577
a(n) = A003557(A276076(n)).
3
1, 1, 1, 1, 3, 3, 1, 1, 1, 1, 3, 3, 5, 5, 5, 5, 15, 15, 25, 25, 25, 25, 75, 75, 1, 1, 1, 1, 3, 3, 1, 1, 1, 1, 3, 3, 5, 5, 5, 5, 15, 15, 25, 25, 25, 25, 75, 75, 7, 7, 7, 7, 21, 21, 7, 7, 7, 7, 21, 21, 35, 35, 35, 35, 105, 105, 175, 175, 175, 175, 525, 525, 49, 49, 49, 49, 147, 147, 49, 49, 49, 49, 147, 147, 245
OFFSET
0,5
FORMULA
a(n) = A003557(A276076(n)).
a(n) = A276076(A276009(n)).
a(n) = A328572(A351576(n)).
a(n) = A085731(A276076(n)) = gcd(A276076(n), A351950(n)).
PROG
(PARI)
A003557(n) = (n/factorback(factorint(n)[, 1]));
A276076(n) = { my(i=0, m=1, f=1, nextf); while((n>0), i=i+1; nextf = (i+1)*f; if((n%nextf), m*=(prime(i)^((n%nextf)/f)); n-=(n%nextf)); f=nextf); m; };
KEYWORD
nonn,base,look
AUTHOR
Antti Karttunen, Apr 01 2022
STATUS
approved