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A156918 Triangle formed by coefficients of the expansion of p(x,n) = (1+x-x^2)^(n+1)*Sum_{j >= 0} (2*j+1)^n*(-x + x^2)^j. 5
1, 1, -1, 1, 1, -6, 7, -2, 1, 1, -23, 46, -47, 26, -3, 1, 1, -76, 306, -536, 459, -232, 82, -4, 1, 1, -237, 1919, -5046, 6965, -5995, 3109, -958, 247, -5, 1, 1, -722, 11265, -44634, 91730, -113538, 90417, -49398, 17778, -3630, 737, -6, 1, 1, -2179, 62836, -381037, 1099549, -1878718, 2123525, -1658537, 898985, -346886, 93377, -13109, 2200, -7, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,6
COMMENTS
Row sums are one.
LINKS
FORMULA
T(n, k) = coefficients of the expansion of p(x, n), where p(x,n) = (1+x-x^2)^(n + 1)*Sum_{j >= 0} (2*j+1)^n*(-x + x^2)^j.
T(n, 1) = (-1)*A060188(n), for n >= 2. - G. C. Greubel, Jan 07 2022
EXAMPLE
Irregular triangle begins as:
1;
1, -1, 1;
1, -6, 7, -2, 1;
1, -23, 46, -47, 26, -3, 1;
1, -76, 306, -536, 459, -232, 82, -4, 1;
1, -237, 1919, -5046, 6965, -5995, 3109, -958, 247, -5, 1;
1, -722, 11265, -44634, 91730, -113538, 90417, -49398, 17778, -3630, 737, -6, 1;
MATHEMATICA
p[x_, n_] = (1+x-x^2)^(n+1)*Sum[(2*k+1)^n*(-x+x^2)^k, {k, 0, Infinity}];
Table[CoefficientList[p[x, n], x], {n, 0, 10}]//Flatten
PROG
(Sage)
def T(n, k): return ( (1+x-x^2)^(n+1)*sum((2*j+1)^n*(x^2-x)^j for j in (0..2*n+1)) ).series(x, 2*n+2).list()[k]
flatten([1]+[[T(n, k) for k in (0..2*n)] for n in (1..12)]) # G. C. Greubel, Jan 07 2022
CROSSREFS
Sequence in context: A244682 A201323 A155490 * A123154 A021602 A198098
KEYWORD
sign,tabf
AUTHOR
Roger L. Bagula, Feb 18 2009
EXTENSIONS
Edited by G. C. Greubel, Jan 07 2022
STATUS
approved

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Last modified March 28 03:28 EDT 2024. Contains 371235 sequences. (Running on oeis4.)