A199858 Decimal expansion of Sum_{n = 1 .. infinity }[ 1 / Sum {i = 1 .. m} d(i)^n] where d(i) are the divisors of n and m = tau(n) is the number of divisors of n.

1, 2, 3, 9, 7, 1, 9, 5, 3, 8, 1, 4, 6, 2, 2, 7, 4, 1, 1, 9, 6, 5, 0, 4, 2, 6, 7, 6, 5, 2, 4, 5, 8, 7, 1, 0, 4, 6, 7, 9, 0, 0, 0, 3, 6, 4, 6, 2, 3, 5, 4, 2, 7, 4, 1, 4, 2, 9, 5, 8, 6, 3, 0, 5, 7, 6, 9, 8, 9, 8, 3, 3, 8, 1, 7, 1, 7, 6, 5, 2, 1, 5, 0, 9, 6, 0, 2, 6, 2, 4, 8, 4, 8, 9, 7, 7, 1, 1, 4, 7, 6, 8, 7, 0, 3

Offset: 1

Author

Michel Lagneau, Nov 28 2011

Keywords

• nonn
• cons

Examples

			1.23971953814622741196504267652458710467...
		

Programs

Mathematica

RealDigits[N[Sum[1/DivisorSigma[n,n],{n,1,100}],130]][[1]]