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A131405
Row sums of triangle A131404.
2
1, 2, 7, 16, 37, 82, 179, 384, 813, 1702, 3531, 7272, 14889, 30342, 61603, 124700, 251825, 507582, 1021535, 2053388, 4123481, 8274002, 16591767, 33254356, 66623317, 133432082, 267164239, 534814024, 1070413693, 2142098602, 4286254091, 8575836312, 17157057669
OFFSET
0,2
FORMULA
From Andrew Howroyd, Aug 09 2018: (Start)
a(n) = 5*a(n-1) - 8*a(n-2) + 3*a(n-3) + 3*a(n-4) - 2*a(n-5).
G.f.: (1 - 3*x + 5*x^2 - 6*x^3 + 4*x^4)/((1 - x)^2*(1 - 2*x)*(1 - x - x^2)).
(End)
EXAMPLE
a(4) = 37 = sum of row 4 terms of triangle A131404: (1 + 11 + 13 + 11 + 1).
PROG
(PARI) Vec((1 - 3*x + 5*x^2 - 6*x^3 + 4*x^4)/((1 - x)^2*(1 - 2*x)*(1 - x - x^2)) + O(x^40)) \\ Andrew Howroyd, Aug 09 2018
CROSSREFS
Row sums of A131404.
Cf. A131403.
Sequence in context: A097442 A345025 A329324 * A269963 A176805 A224227
KEYWORD
nonn
AUTHOR
Gary W. Adamson, Jul 07 2007
EXTENSIONS
Terms a(10) and beyond from Andrew Howroyd, Aug 09 2018
STATUS
approved