A191278 - OEIS

A191278

Count of Mosaic numbers that equal n.

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

1,6

COMMENTS

The number of solutions x to A000026(x)=n.

LINKS

R. J. Mathar, Table of n, a(n) for n = 1..1000

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

Adjacent sequences: A191275 A191276 A191277 * A191279 A191280 A191281

KEYWORD

nonn,easy

AUTHOR

R. J. Mathar, May 29 2011

STATUS

approved