A069061 Sum of divisors of 2^n+1.
4, 6, 13, 18, 48, 84, 176, 258, 800, 1302, 2736, 4356, 10928, 20520, 51792, 65538, 174768, 351120, 699056, 1110276, 3100240, 5048232, 11184816, 17041416, 49012992, 82623888, 211053040, 284225796, 727960800, 1494039792, 2863311536, 4301668356, 12611914848, 20788904016
Offset: 1
Keywords
Links
- Max Alekseyev, Table of n, a(n) for n = 1..1128 (terms 1..1062 from Amiram Eldar)
Crossrefs
Programs
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Mathematica
DivisorSigma[1, 2^Range[50] + 1] (* Paolo Xausa, Jul 05 2024 *)
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PARI
a(n) = sigma(2^n+1); \\ Michel Marcus, Nov 24 2013
Formula
a(n) = sigma(2^n+1).
Extensions
More terms from Amiram Eldar, Oct 04 2019