The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 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. 0
 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 (list; constant; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS EXAMPLE 1.23971953814622741196504267652458710467... MATHEMATICA RealDigits[N[Sum[1/DivisorSigma[n, n], {n, 1, 100}], 130]][[1]] CROSSREFS Sequence in context: A288842 A108694 A267896 * A199963 A016634 A244257 Adjacent sequences:  A199855 A199856 A199857 * A199859 A199860 A199861 KEYWORD nonn,cons AUTHOR Michel Lagneau, Nov 28 2011 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified August 13 04:54 EDT 2020. Contains 336442 sequences. (Running on oeis4.)