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A229281
Number of ascending runs in {1,...,7}^n.
2
0, 7, 77, 735, 6517, 55223, 453789, 3647119, 28824005, 224827239, 1735205101, 13276336703, 100843663893, 761270796055, 5716451614013, 42728053589487, 318086621166181, 2359538070441671, 17447288549040525, 128644674234925471, 946108300385970869
OFFSET
0,2
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
KEYWORD
nonn,easy
AUTHOR
Alois P. Heinz, Sep 18 2013
STATUS
approved