A171471 a(n) = 6*a(n-1)-8*a(n-2)-9 for n > 2; a(0) = 35, a(1) = 225, a(2) = 837.

35, 225, 837, 3213, 12573, 49725, 197757, 788733, 3150333, 12592125, 50350077, 201363453, 805380093, 3221372925, 12885196797, 51540197373, 206159609853, 824636080125, 3298539601917, 13194148970493, 52776577007613

Offset

0,1

Comments

Related to Reverse and Add trajectory of 22 in base 2: A061561(4*n+1) = a(n).

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..500

Index entries for linear recurrences with constant coefficients, signature (7,-14,8).

Formula

a(n) = 48*4^n+18*2^n-3 for n > 0.

G.f.: (35-20*x-248*x^2+224*x^3)/((1-x)*(1-2*x)*(1-4*x)).

Mathematica

LinearRecurrence[{7, -14, 8}, {35, 225, 837, 3213}, 30] (* Harvey P. Dale, Mar 22 2018 *)

Prog

(PARI) {m=22; v=concat([35, 225, 837], vector(m-3)); for(n=4, m, v[n]=6*v[n-1]-8*v[n-2]-9); v}

Crossrefs

Cf. A061561, A171470, A171472, A171473.

Sequence in context: A257758 A195968 A104474 * A223648 A219474 A220208

Adjacent sequences: A171468 A171469 A171470 * A171472 A171473 A171474

Keyword

nonn,easy

Author

Klaus Brockhaus, Dec 09 2009

Status

approved