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A328098 If A327928(n) is zero, a(n) = A003415(n), otherwise a(n) = A327858(n) = gcd(A003415(n), A276086(n)). 7
0, 1, 1, 1, 1, 5, 1, 1, 6, 7, 1, 1, 1, 9, 1, 1, 1, 21, 1, 1, 10, 13, 1, 1, 10, 15, 3, 1, 1, 31, 1, 5, 14, 19, 1, 1, 1, 21, 1, 1, 1, 41, 1, 1, 39, 25, 1, 7, 14, 45, 5, 7, 1, 3, 1, 1, 22, 31, 1, 1, 1, 33, 51, 1, 18, 61, 1, 1, 26, 59, 1, 1, 1, 39, 55, 5, 18, 71, 1, 1, 1, 43, 1, 1, 22, 45, 1, 35, 1, 123, 5, 1, 34, 49, 1, 1, 1, 77, 75, 35, 1, 91, 1, 1, 71 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,6
COMMENTS
After zero, sequence contains only terms of A048103.
LINKS
PROG
(PARI)
A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));
A129251(n) = { my(f = factor(n)); sum(k=1, #f~, (f[k, 2]>=f[k, 1])); };
A276086(n) = { my(i=0, m=1, pr=1, nextpr); while((n>0), i=i+1; nextpr = prime(i)*pr; if((n%nextpr), m*=(prime(i)^((n%nextpr)/pr)); n-=(n%nextpr)); pr=nextpr); m; };
A328098(n) = if(1==n, 0, my(u=A003415(n)); if(!A129251(u), u, gcd(u, A276086(u))));
CROSSREFS
Sequence in context: A298635 A171146 A174038 * A200401 A214228 A324385
KEYWORD
nonn
AUTHOR
Antti Karttunen, Oct 07 2019
STATUS
approved

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Last modified April 24 10:11 EDT 2024. Contains 371935 sequences. (Running on oeis4.)