A108466 -id:A108466 - cp's OEIS frontend

A108467 a(n) = A108466(A025487).

1, 1, 2, 3, 4, 11, 9, 35, 25, 20, 55, 106, 132, 45, 222, 303, 566, 100, 808, 918, 827, 339, 1086, 2128, 220, 2682, 4790, 2173, 2453, 4561, 7269, 478, 8335, 21093, 5515, 13223, 17135, 7997, 23079, 1025, 29229, 24503, 22165, 21597, 82298, 13595, 59613, 59196

Offset: 0

Christian G. Bower, Jun 03 2005

nonn

Number of factorizations of (n,n) into pairs (i,j) by prime signature.

Cf. A108460.

More terms from David Wasserman, May 19 2008

A108465 Table read by antidiagonals: T(n,k) (n>=2) = number of factorizations of (n,k) into pairs (i,j) with i,j>1.

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 3, 1, 2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, 1, 3, 1, 3, 1, 2, 1, 1, 1, 1, 1, 1, 2, 1, 1, 2, 1, 1, 1, 1, 1, 1, 3, 1, 3, 1, 4, 1, 3, 1, 3, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 1, 1, 1, 1, 1, 1

Offset: 2

Christian G. Bower, Jun 03 2005

(a,b)*(x,y)=(a*x,b*y).

			1 1 1 1 1 ...
1 1 1 1 1 ...
1 1 2 1 2 ...
1 1 1 1 1 ...
1 1 2 1 3 ...
(8,6)=(4,3)*(2,2)=(4,2)*(2,3), so a(8,6)=3.

Cf. A108461. Columns 4, 6: A038548 (n>1), A032741. Main diagonal: A108466.

Dirichlet g.f.: A(s, t) = exp(B(s, t)/1 + B(2*s, 2*t)/2 + B(3*s, 3*t)/3 + ...) where B(s, t) = (zeta(s)-1)*(zeta(t)-1).

cp's OEIS Frontend

A108467 a(n) = A108466(A025487).

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