A279543 a(n) = a(n-1) + 3^n * a(n-2) with a(0) = 1 and a(1) = 1.

1, 1, 10, 37, 847, 9838, 627301, 22143007, 4137864868, 439978671649, 244776761262181, 78185678507867584, 130162592460442600405, 124783388108159412726037, 622688428086038843429228482, 1791127919536971393223950620041

Offset

0,3

Comments

The Rogers-Ramanujan continued fraction is defined by R(q) = q^(1/5)/(1+q/(1+q^2/(1+q^3/(1+ ... )))). The limit of a(n)/A015460(n+2) is 3^(-1/5) * R(3).

Links

Seiichi Manyama, Table of n, a(n) for n = 0..90

Eric Weisstein's World of Mathematics, Rogers-Ramanujan Continued Fraction

Example

1/1 = a(0)/A015460(2).
1/(1+3/1) = 1/4 = a(1)/A015460(3).
1/(1+3/(1+3^2/1)) = 10/13 = a(2)/A015460(4).
1/(1+3/(1+3^2/(1+3^3/1))) = 37/121 = a(3)/A015460(5).

Mathematica

RecurrenceTable[{a[n] == a[n - 1] + 3^n*a[n - 2], a[0] == 1, a[1] == 1}, a, {n, 15}] (* Michael De Vlieger, Dec 31 2016 *)

Crossrefs

Cf. A015460, A128915.

Cf. similar sequences with the recurrence a(n-1) + q^n * a(n-2) for n>1, a(0)=1 and a(1)=1: A280294 (q=2), this sequence (q=3), A280340 (q=10).

Sequence in context: A071261 A129426 A215881 * A065009 A031430 A154517

Adjacent sequences: A279540 A279541 A279542 * A279544 A279545 A279546

Keyword

nonn

Author

Seiichi Manyama, Dec 31 2016

Status

approved