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A135592
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a(n) is number of earlier terms equal to number of prime divisors of n.
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1
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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
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OFFSET
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1,3
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COMMENTS
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Similar to A125087, but instead of exponents, we use number of prime divisors.
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LINKS
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EXAMPLE
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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).
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PROG
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(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);
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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