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A131244 Row sums of triangle A131243. 5
1, 3, 6, 14, 30, 67, 146, 322, 705, 1549, 3396, 7453, 16346, 35861, 78659, 172549, 378487, 830234, 1821136, 3994730, 8762543, 19220904, 42161568, 92482585, 202863051, 444985664, 976088107, 2141075804, 4696507779 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

A131246 is a companion sequence.

LINKS

Table of n, a(n) for n=0..28.

Index entries for linear recurrences with constant coefficients, signature (2,2,-3,-1).

FORMULA

G.f. ( 1+x-x^3-2*x^2 ) / ( 1-2*x-2*x^2+3*x^3+x^4 ). - R. J. Mathar, Jan 29 2011

EXAMPLE

a(4) = 30 = sum of row 4 terms of A131243: (8 + 7 + 10 + 4 + 1).

MAPLE

A065941 := proc(n, k) binomial(n-floor((k+1)/2), floor(k/2)) ; end proc:

A131243 := proc(n, k) local a, j ; a := 0 ; for j from k to n do a := a+ A065941(n, j)*A065941(j, k) ; end do: a ; end proc:

A131244 := proc(n) add(A131243(n, k), k=0..n) ; end proc:

seq(A131244(n), n=0..50) ; # R. J. Mathar, Jan 29 2011

PROG

(PARI) Vec((1+x-x^3-2*x^2)/(1-2*x-2*x^2+3*x^3+x^4)+O(x^99)) \\ Charles R Greathouse IV, Jun 12 2015

CROSSREFS

Cf. A131243, A131245, A131246.

Sequence in context: A192672 A175656 A196450 * A077926 A091601 A339154

Adjacent sequences:  A131241 A131242 A131243 * A131245 A131246 A131247

KEYWORD

nonn,easy

AUTHOR

Gary W. Adamson, Jun 22 2007

STATUS

approved

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Last modified April 17 04:36 EDT 2021. Contains 343059 sequences. (Running on oeis4.)