A229281 Number of ascending runs in {1,...,7}^n.

0, 7, 77, 735, 6517, 55223, 453789, 3647119, 28824005, 224827239, 1735205101, 13276336703, 100843663893, 761270796055, 5716451614013, 42728053589487, 318086621166181, 2359538070441671, 17447288549040525, 128644674234925471, 946108300385970869

Offset

0,2

Links

Alois P. Heinz, Table of n, a(n) for n = 0..1000

Index entries for linear recurrences with constant coefficients, signature (14,-49).

Formula

G.f.: -7*(3*x-1)*x/(7*x-1)^2.

a(n) = 7^(n-1)*(4*n+3) for n>0, a(0) = 0.

Maple

a:= n-> `if`(n=0, 0, 7^(n-1)*(4*n+3)):
seq(a(n), n=0..30);

Crossrefs

Column k=7 of A229079.

Sequence in context: A228414 A043042 A191465 * A144071 A366596 A061546

Adjacent sequences: A229278 A229279 A229280 * A229282 A229283 A229284

Keyword

nonn,easy

Author

Alois P. Heinz, Sep 18 2013

Status

approved