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A081893
Third binomial transform of C(n+2,2).
3
1, 6, 33, 172, 864, 4224, 20224, 95232, 442368, 2031616, 9240576, 41680896, 186646528, 830472192, 3674210304, 16173236224, 70866960384, 309237645312, 1344324763648, 5823975653376, 25151328485376, 108301895335936
OFFSET
0,2
COMMENTS
Binomial transform of A081892.
3rd binomial transform of C(n+2,2), A000217.
4th binomial transform of (1,2,1,0,0,0,.....)
FORMULA
a(n) = 4^n*(n^2 + 15*n + 32)/32.
G.f.: (1 - 3*x)^2/(1 - 4*x)^3.
E.g.f.: (2 + 4*x + x^2)*exp(4*x)/2. - G. C. Greubel, Oct 18 2018
MATHEMATICA
LinearRecurrence[{12, -48, 64}, {1, 6, 33}, 50] (* G. C. Greubel, Oct 18 2018 *)
PROG
(PARI) x='x+O('x^30); Vec((1-3*x)^2/(1-4*x)^3) \\ G. C. Greubel, Oct 18 2018
(Magma) m:=30; R<x>:=PowerSeriesRing(Integers(), m); Coefficients(R!((1-3*x)^2/(1-4*x)^3)); // G. C. Greubel, Oct 18 2018
CROSSREFS
Cf. A081894.
Sequence in context: A084153 A086314 A086091 * A106850 A284076 A094165
KEYWORD
nonn,easy
AUTHOR
Paul Barry, Mar 30 2003
STATUS
approved