A096856 a(n) = A062402(2^n+1).

1, 3, 7, 12, 31, 42, 124, 224, 511, 847, 1953, 2688, 12264, 18816, 29127, 72540, 131071, 195048, 558523, 1077440, 3164112, 4552020, 10890040, 10342080, 54525848, 73260781, 155671040, 318848400, 1080311232, 964580240, 3070642080, 4340711424, 13722819600, 19039027200

Offset

0,2

Links

Amiram Eldar, Table of n, a(n) for n = 0..372

Formula

a(n) = A000203(A053285(n)). - Amiram Eldar, Jun 04 2024

Mathematica

Table[DivisorSigma[1, EulerPhi[2^n + 1]], {n, 0, 30}]

Crossrefs

Cf. A000203, A053285, A062401, A062402, A053287, A096853, A096854, A096855.

Sequence in context: A047068 A167490 A081533 * A347862 A345260 A108154

Adjacent sequences: A096853 A096854 A096855 * A096857 A096858 A096859

Keyword

nonn

Author

Labos Elemer, Jul 19 2004

Extensions

Offset changed to 0, a(0) prepended and three more terms added by Amiram Eldar, Jun 04 2024

Status

approved