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A171215 Row cubed sums of triangle of Lucas polynomials (A034807) for n>0: Sum_{k=0..[n/2]} A034807(n,k)^3. 2
1, 9, 28, 73, 251, 954, 3431, 12617, 48142, 184509, 710755, 2768410, 10857575, 42779655, 169411778, 673898825, 2690398105, 10776264120, 43294049155, 174399508573, 704214759836, 2849828137869, 11555835845903, 46943852758298 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..160

FORMULA

Equals the logarithmic derivative of A171185.

EXAMPLE

L.g.f.: L(x) = x + 9*x^2/2 + 28*x^3/3 + 73*x^4/4 + 251*x^5/5 +...

exp(L(x)) = 1 + x + 5*x^2 + 14*x^3 + 40*x^4 + 126*x^5 + 408*x^6 +...+ A171185(n)*x^n +...

PROG

(PARI) {a(n)=sum(k=0, n\2, (binomial(n-k, k)+binomial(n-k-1, k-1))^3)}

(Maxima) makelist(sum((binomial(n-k, k)+binomial(n-k-1, k-1))^3, k, 0, floor(n/2)), n, 1, 24);  [Bruno Berselli, May 19 2011]

(MAGMA) A034807cubed:=func< n | [(Binomial(n-k, k)+Binomial(n-k-1, k-1))^3: k in [0..Floor(n/2)]] >; [&+A034807cubed(n): n in [1..24]];  // Bruno Berselli, May 19 2011

CROSSREFS

Cf. A171185, A132461, A171187.

Sequence in context: A017669 A277065 A001158 * A296601 A294567 A053819

Adjacent sequences:  A171212 A171213 A171214 * A171216 A171217 A171218

KEYWORD

nonn

AUTHOR

Paul D. Hanna, Dec 14 2009

STATUS

approved

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Last modified January 26 05:10 EST 2020. Contains 331273 sequences. (Running on oeis4.)