A278612 Sum of terms in level n of TRIP - Stern sequence associated with permutation triple (e, e, e).

3, 8, 22, 60, 162, 436, 1174, 3164, 8530, 22996, 61990, 167100, 450434, 1214196, 3273014, 8822812, 23782962, 64109844, 172815814, 465845884, 1255743842, 3385009204, 9124701142, 24596733916, 66303466770, 178729002068, 481785610086, 1298711297084, 3500833146178, 9436918539636, 25438353615990

Offset: 0

Author

Ilya Amburg, Nov 23 2016

Keywords

• nonn
• easy

Links

• Colin Barker, Table of n, a(n) for n = 0..1000
• I. Amburg, K. Dasaratha, L. Flapan, T. Garrity, C. Lee, C. Mihailak, N. Neumann-Chun, S. Peluse, M. Stoffregen, Stern Sequences for a Family of Multidimensional Continued Fractions: TRIP-Stern Sequences, arXiv:1509.05239 [math.CO], 17 Sep 2015.
• Index entries for linear recurrences with constant coefficients, signature (4,-5,4).

Crossrefs

Cf. A278613, A278614, A278615, A278616.

Programs

PARI

Vec((3 - 4*x + 5*x^2) / (1 - 4*x + 5*x^2 - 4*x^3) + O(x^40)) \\ Colin Barker, Jan 09 2018

Formula

a(n) = A271896(n) + A271897(n) + A271898(n). - R. J. Mathar, Dec 02 2016

From Colin Barker, Jan 09 2018: (Start)

G.f.: (3 - 4*x + 5*x^2) / (1 - 4*x + 5*x^2 - 4*x^3).

a(n) = 4*a(n-1) - 5*a(n-2) + 4*a(n-3) for n>2.

(End)