A147536 a(n) = 4*3^n+4^n.

5, 16, 52, 172, 580, 1996, 7012, 25132, 91780, 340876, 1284772, 4902892, 18902980, 73486156, 287567332, 1131137452, 4467154180, 17696429836, 70269158692, 279526952812, 1113458765380

Offset

0,1

Links

Table of n, a(n) for n=0..20.

Formula

a(n)=7*a(n-1)-12*a(n-2) = 4*3^n+4^n. G.f.: (5-19x)/((1-4x)(1-3x)). [From R. J. Mathar, Nov 09 2008]

Crossrefs

Sequence in context: A007343 A371437 A274492 * A347434 A173871 A108300

Adjacent sequences: A147533 A147534 A147535 * A147537 A147538 A147539

Keyword

nonn,easy,less

Author

Roger L. Bagula, Nov 06 2008

Extensions

Meaningful name from Joerg Arndt, Dec 26 2022

Status

approved