A072057 Sum of divisors of 2*prime(n)+1.

6, 8, 12, 24, 24, 40, 48, 56, 48, 60, 104, 124, 84, 120, 120, 108, 144, 168, 240, 168, 228, 216, 168, 180, 336, 240, 312, 264, 296, 228, 432, 264, 372, 416, 336, 408, 624, 440, 408, 348, 360, 532, 384, 572, 480, 640, 624, 600, 672, 720, 468

Offset

1,1

Links

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

Example

Divisors of A072055(8)=2*A000040(8)+1=2*19+1=39: {1,3,13,39}, therefore a(8)=1+3+13+39=56.

Mathematica

DivisorSigma[1, #]&/@(2Prime[Range[60]]+1) (* Harvey P. Dale, Sep 17 2013 *)

Prog

(Haskell)
a072057 = a000203 . a072055  -- Reinhard Zumkeller, Oct 10 2013

Crossrefs

a(n)=A000203(A072055(n)), A000040, A072056.

Sequence in context: A315871 A315872 A315873 * A212351 A361968 A327240

Adjacent sequences: A072054 A072055 A072056 * A072058 A072059 A072060

Keyword

nonn

Author

Reinhard Zumkeller, Jun 11 2002

Status

approved