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A331175
Number of values of k, 1 <= k <= n, with A109395(k) = A109395(n), where A109395(n) = n/gcd(n, phi(n)).
6
1, 1, 1, 2, 1, 2, 1, 3, 3, 2, 1, 4, 1, 2, 1, 4, 1, 5, 1, 3, 3, 2, 1, 6, 4, 2, 7, 4, 1, 2, 1, 5, 1, 2, 1, 8, 1, 2, 3, 5, 1, 5, 1, 3, 3, 2, 1, 9, 6, 6, 1, 4, 1, 10, 4, 7, 3, 2, 1, 4, 1, 2, 8, 6, 1, 2, 1, 3, 1, 2, 1, 11, 1, 2, 5, 4, 1, 5, 1, 7, 12, 2, 1, 9, 1, 2, 1, 5, 1, 6, 1, 3, 3, 2, 1, 13, 1, 10, 3, 8, 1, 2, 1, 6, 3
OFFSET
1,4
COMMENTS
Ordinal transform of A109395.
LINKS
FORMULA
For n >= 1, a(2^n) = n, a(A003277(n)) = 1.
PROG
(PARI)
up_to = 65537;
ordinal_transform(invec) = { my(om = Map(), outvec = vector(length(invec)), pt); for(i=1, length(invec), if(mapisdefined(om, invec[i]), pt = mapget(om, invec[i]), pt = 0); outvec[i] = (1+pt); mapput(om, invec[i], (1+pt))); outvec; };
A109395(n) = n/gcd(n, eulerphi(n));
v331175 = ordinal_transform(vector(up_to, n, A109395(n)));
A331175(n) = v331175[n];
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jan 11 2020
STATUS
approved