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A135592 a(n) is number of earlier terms equal to number of prime divisors of n. 1
1, 1, 2, 2, 2, 3, 2, 2, 2, 6, 2, 7, 2, 8, 8, 2, 2, 10, 2, 11, 11, 11, 2, 12, 2, 13, 2, 14, 2, 1, 3, 3, 15, 15, 15, 15, 3, 15, 15, 15, 3, 5, 3, 15, 15, 15, 3, 15, 3, 15, 15, 15, 3, 15, 15, 15, 15, 15, 3, 10, 3, 15, 15, 3, 15, 12, 3, 15, 15, 13, 3, 15, 3, 15, 15, 15, 15, 15, 3, 15, 3, 15, 3, 18 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Similar to A135352, but instead of exponents, we use number of prime divisors.

LINKS

Katarzyna Matylla, Table of n, a(n) for n = 1..1000

EXAMPLE

a(12)=7 because 12 has 2 prime divisors (2 and 3) and there are 7 2's in a(1), a(2),..., a(11).

PROG

Maxima: max:1000; f:makelist(0, i, 1, max); apr:makelist(0, i, 1, max); f[1]:1; apr[2]:1; print(1, 1); for n:2 through max do block(f[n]:apr[length(ifactors(n))+1], apr[f[n]+1]:apr[f[n]+1]+1);

CROSSREFS

Cf. A125087, A135352, A135591.

Sequence in context: A301375 A325273 A279408 * A022912 A318955 A173883

Adjacent sequences:  A135589 A135590 A135591 * A135593 A135594 A135595

KEYWORD

nonn

AUTHOR

Katarzyna Matylla, Feb 25 2008

STATUS

approved

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Last modified April 22 08:06 EDT 2019. Contains 322329 sequences. (Running on oeis4.)