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A191278 Count of Mosaic numbers that equal n. 1
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 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,6
COMMENTS
The number of solutions x to A000026(x)=n.
LINKS
FORMULA
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]
MAPLE
A191278 := proc(n)
local f, beta, a, j ;
f := ifactors(n)[2] ;
beta := A073093(n) ;
a := 1/beta ;
for j in ifactors(n)[2] do
a := a*binomial(beta, op(2, j) ) ;
end do:
a ;
end proc:
CROSSREFS
Sequence in context: A291448 A114006 A050328 * A363085 A359577 A030401
KEYWORD
nonn,easy
AUTHOR
R. J. Mathar, May 29 2011
STATUS
approved

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Last modified May 11 15:49 EDT 2024. Contains 372409 sequences. (Running on oeis4.)