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A154918
Triangle, read by rows, T(n, k) = binomial(4*n, 3*k) + binomial(4*n, 3*(n-k)).
1
2, 5, 5, 29, 112, 29, 221, 1144, 1144, 221, 1821, 12000, 16016, 12000, 1821, 15505, 127110, 206720, 206720, 127110, 15505, 134597, 1309528, 2838752, 2615008, 2838752, 1309528, 134597, 1184041, 13126386, 37818900, 37328655, 37328655, 37818900, 13126386, 1184041
OFFSET
0,1
COMMENTS
Row sums are: {2, 10, 170, 2730, 43658, 698670, 11180762, 178915964, 2862907786,
45809074626, 732970281870, ...}.
FORMULA
T(n, k) = binomial(4*n, 3*k) + binomial(4*n, 3*(n-k)).
EXAMPLE
Triangle begins as:
2;
5, 5;
29, 112, 29;
221, 1144, 1144, 221;
1821, 12000, 16016, 12000, 1821;
15505, 127110, 206720, 206720, 127110, 15505;
MAPLE
b:=binomial; seq(seq( b(4*n, 3*k) + b(4*n, 3*(n-k)), k=0..n), n=0..10); # G. C. Greubel, Dec 02 2019
MATHEMATICA
Table[Binomial[4*n, 3*k] +Binomial[4*n, 3*(n-k)], {n, 0, 10}, {k, 0, n}]//Flatten (* modified by G. C. Greubel, Dec 02 2019 *)
PROG
(PARI) T(n, k) = my(b=binomia); b(4*n, 3*k) + b(4*n, 3*(n-k)); \\ G. C. Greubel, Dec 02 2019
(Magma) B:=Binomial; [B(4*n, 3*k) + B(4*n, 3*(n-k)): k in [0..n], n in [0..10]]; // G. C. Greubel, Dec 02 2019
(Sage) b=binomial; [[b(4*n, 3*k) + b(4*n, 3*(n-k)) for k in (0..n)] for n in (0..10)] # G. C. Greubel, Dec 02 2019
(GAP) B:=Binomial;; Flat(List([0..10], n-> List([0..n], k-> B(4*n, 3*k) + B(4*n, 3*(n-k)) ))); # G. C. Greubel, Dec 02 2019
CROSSREFS
Sequence in context: A238879 A286258 A297446 * A176862 A352392 A176081
KEYWORD
nonn,tabl
AUTHOR
Roger L. Bagula, Jan 17 2009
EXTENSIONS
Edited by G. C. Greubel, Dec 02 2019
STATUS
approved