A357451 Number of compositions (ordered partitions) of n into tribonacci numbers 1,2,4,7,13,24, ... (A000073).

1, 1, 2, 3, 6, 10, 18, 32, 57, 101, 179, 318, 564, 1002, 1778, 3157, 5603, 9947, 17656, 31342, 55635, 98759, 175308, 311191, 552400, 980571, 1740625, 3089803, 5484750, 9736045, 17282576, 30678512, 54457808, 96668726, 171597851, 304605465, 540708924

Offset

0,3

Links

Table of n, a(n) for n=0..36.

Formula

G.f.: 1 / (1 - Sum_{k>=3} x^A000073(k)).

Mathematica

A000073[0] = A000073[1] = 0; A000073[2] = 1; A000073[n_] := A000073[n] = A000073[n - 1] + A000073[n - 2] + A000073[n - 3]; nmax = 36; CoefficientList[Series[1/(1 - Sum[x^A000073[k], {k, 3, 20}]), {x, 0, nmax}], x]

Crossrefs

Cf. A000073, A076739, A117546, A240844, A357453, A357455.

Sequence in context: A147852 A061279 A018073 * A224342 A181649 A052972

Adjacent sequences: A357448 A357449 A357450 * A357452 A357453 A357454

Keyword

nonn

Author

Ilya Gutkovskiy, Sep 29 2022

Status

approved