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A324188 a(n) = A324121(A163511(n)). 5
1, 1, 1, 2, 1, 1, 12, 2, 1, 4, 3, 1, 4, 12, 2, 2, 3, 1, 24, 4, 1, 2, 3, 3, 12, 6, 24, 4, 6, 4, 8, 2, 1, 2, 3, 1, 8, 24, 4, 4, 3, 1, 12, 6, 1, 6, 3, 1, 4, 120, 18, 2, 24, 24, 16, 4, 10, 2, 48, 4, 56, 12, 4, 2, 1, 1, 12, 6, 1, 2, 1, 1, 24, 12, 48, 40, 12, 8, 16, 4, 1, 20, 3, 3, 4, 36, 6, 14, 15, 3, 36, 6, 21, 2, 3, 3, 36, 6, 720, 8, 6, 4, 24, 6, 120, 12 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,4
LINKS
FORMULA
a(n) = A324121(A163511(n)) = gcd(A324184(n), A163511(n)*A324183(n)).
For n > 0, a(n) = A324058(A054429(n)).
PROG
(PARI)
A163511(n) = if(!n, 1, my(p=2, t=1); while(n>1, if(!(n%2), (t*=p), p=nextprime(1+p)); n >>= 1); (t*p));
A324121(n) = gcd(sigma(n), n*numdiv(n));
(PARI)
A324183(n) = if(!n, 1, n = ((3<<#binary(n\2))-n-1); my(e=0, m=1); while(n>0, if(!(n%2), m *= (1+e); e=0, e++); n >>= 1); (m*(1+e)));
A324184(n) = if(!n, 1, my(p=2, mp=p*p, m=1); while(n>1, if(n%2, p=nextprime(1+p); mp = p*p, if((2==n)||!(n%4), mp *= p, m *= (mp-1)/(p-1))); n >>= 1); (m*(mp-1)/(p-1)));
A324188(n) = gcd(A324184(n), A163511(n)*A324183(n));
CROSSREFS
Sequence in context: A197648 A066094 A160625 * A297762 A010246 A186430
KEYWORD
nonn
AUTHOR
Antti Karttunen, Feb 17 2019
STATUS
approved

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Last modified March 4 05:23 EST 2024. Contains 370522 sequences. (Running on oeis4.)