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A191278
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Count of Mosaic numbers that equal n.
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1
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1, 1, 1, 1, 1, 3, 1, 1, 1, 3, 1, 6, 1, 3, 3, 1, 1, 6, 1, 6, 3, 3, 1, 10, 1, 3, 1, 6, 1, 16, 1, 1, 3, 3, 3, 20, 1, 3, 3, 10, 1, 16, 1, 6, 6, 3, 1, 15, 1, 6, 3, 6, 1, 10, 3, 10, 3, 3, 1, 50, 1, 3, 6, 1, 3, 16, 1, 6, 3, 16, 1, 50, 1, 3, 6, 6, 3, 16, 1, 15, 1, 3, 1, 50, 3, 3, 3, 10, 1, 50
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OFFSET
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1,6
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COMMENTS
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The number of solutions x to A000026(x)=n.
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LINKS
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FORMULA
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Let n=product_j p_j^e(j) be the prime factorization of n and beta=A073093(n). Then a(n)*beta = product_j binomial(beta,e(j)). [Gordon-Robertson in A000026, Theorem 1]
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MAPLE
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local f, beta, a, j ;
f := ifactors(n)[2] ;
a := 1/beta ;
for j in ifactors(n)[2] do
a := a*binomial(beta, op(2, j) ) ;
end do:
a ;
end proc:
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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