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A324192
Number of distinct values A297167 obtains over divisors > 1 of n, minus number of distinct prime factors of n: a(n) = A324190(n) - A001221(n).
5
0, 0, 0, 1, 0, 0, 0, 2, 1, 0, 0, 1, 0, 0, 0, 3, 0, 1, 0, 2, 0, 0, 0, 2, 1, 0, 2, 2, 0, 0, 0, 4, 0, 0, 0, 2, 0, 0, 0, 3, 0, 0, 0, 2, 1, 0, 0, 3, 1, 1, 0, 2, 0, 2, 0, 4, 0, 0, 0, 1, 0, 0, 2, 5, 0, 0, 0, 2, 0, 0, 0, 3, 0, 0, 1, 2, 0, 0, 0, 4, 3, 0, 0, 2, 0, 0, 0, 4, 0, 1, 0, 2, 0, 0, 0, 4, 0, 1, 2, 3, 0, 0, 0, 4, 0
OFFSET
1,8
FORMULA
a(n) = A324190(n) - A001221(n).
a(n) >= A324179(n).
PROG
(PARI)
A061395(n) = if(1==n, 0, primepi(vecmax(factor(n)[, 1])));
A297167(n) = if(1==n, 0, (A061395(n) + (bigomega(n)-omega(n)) - 1));
A324190(n) = #Set(apply(A297167, select(d -> d>1, divisors(n))));
A324192(n) = (A324190(n)-omega(n));
CROSSREFS
Sequence in context: A368251 A183094 A373968 * A108730 A056973 A107782
KEYWORD
nonn
AUTHOR
Antti Karttunen, Feb 19 2019
STATUS
approved