A139243 Second differences of Mersenne numbers A001348, divided by 4.

5, 18, 456, 1056, 29184, 67584, 1867776, 130154496, 270532608, 33420214272, 481573208064, 1133871366144, 31336081391616, 2183630092763136, 139646772820574208, 290482175965396992, 35884681830888112128, 517085294816170868736, 1217485108864830406656

Offset

1,1

Links

Paolo Xausa, Table of n, a(n) for n = 1..450

Formula

a(n) = A139241(n)/4 = A139242(n)/2.

Mathematica

Differences[2^Prime[Range[25]]-1, 2]/4 (* Paolo Xausa, Oct 20 2023 *)

Crossrefs

Cf. A001348, A139237, A139239, A139240, A139241, A139242.

Sequence in context: A203180 A359616 A359560 * A347670 A139237 A317541

Adjacent sequences: A139240 A139241 A139242 * A139244 A139245 A139246

Keyword

easy,nonn

Author

Omar E. Pol, Apr 19 2008

Extensions

More terms from Alois P. Heinz, Mar 13 2020

Status

approved