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A247453 T(n,k) = binomial(n,k)*A000111(n-k)*(-1)^(n-k), 0 <= k <= n. 6
1, -1, 1, 1, -2, 1, -2, 3, -3, 1, 5, -8, 6, -4, 1, -16, 25, -20, 10, -5, 1, 61, -96, 75, -40, 15, -6, 1, -272, 427, -336, 175, -70, 21, -7, 1, 1385, -2176, 1708, -896, 350, -112, 28, -8, 1, -7936, 12465, -9792, 5124, -2016, 630, -168, 36, -9, 1, 50521 (list; table; graph; refs; listen; history; text; internal format)
OFFSET
0,5
COMMENTS
Matrix inverse of A109449, the unsigned version of this sequence. More precisely, consider both of these triangles as the nonzero lower left of an infinite square array / matrix, filled with zeros above/right of the diagonal. Then these are mutually inverse of each other; in matrix notation: A247453 . A109449 = A109449 . A247453 = Identity matrix. In more conventional notation, for any m,n >= 0, Sum_{k=0..n} A247453(n,k)*A109449(k,m) = Sum_{k=0..n} A109449(n,k)*A247453(k,m) = delta(m,n), the Kronecker delta (= 1 if m = n, 0 else). - M. F. Hasler, Oct 06 2017
LINKS
J. Millar, N. J. A. Sloane and N. E. Young, A new operation on sequences: the Boustrophedon transform, J. Combin. Theory, 17A 44-54 1996 (Abstract, pdf, ps).
FORMULA
T(n,k) = (-1)^(n-k) * A007318(n,k) * A000111(n-k), k = 0..n;
T(n,k) = (-1)^(n-k) * A109449(n,k); A109449(n,k) = abs(T(n,k));
abs(sum of row n) = A062162(n);
Sum_{k=0..n} T(n,k)*A000111(k) = 0^n.
EXAMPLE
. 0: 1
. 1: -1 1
. 2: 1 -2 1
. 3: -2 3 -3 1
. 4: 5 -8 6 -4 1
. 5: -16 25 -20 10 -5 1
. 6: 61 -96 75 -40 15 -6 1
. 7: -272 427 -336 175 -70 21 -7 1
. 8: 1385 -2176 1708 -896 350 -112 28 -8 1
. 9: -7936 12465 -9792 5124 -2016 630 -168 36 -9 1
. 10: 50521 -79360 62325 -32640 12810 -4032 1050 -240 45 -10 1 .
MATHEMATICA
a111[n_] := n! SeriesCoefficient[(1+Sin[x])/Cos[x], {x, 0, n}];
T[n_, k_] := (-1)^(n-k) Binomial[n, k] a111[n-k];
Table[T[n, k], {n, 0, 10}, {k, 0, n}] // Flatten (* Jean-François Alcover, Aug 03 2018 *)
PROG
(Haskell)
a247453 n k = a247453_tabl !! n !! k
a247453_row n = a247453_tabl !! n
a247453_tabl = zipWith (zipWith (*)) a109449_tabl a097807_tabl
(PARI) A247453(n, k)=(-1)^(n-k)*binomial(n, k)*if(n>k, 2*abs(polylog(k-n, I)), 1) \\ M. F. Hasler, Oct 06 2017
CROSSREFS
Sequence in context: A291980 A238281 A080850 * A109449 A129570 A238385
KEYWORD
sign,tabl
AUTHOR
Reinhard Zumkeller, Sep 17 2014
EXTENSIONS
Edited by M. F. Hasler, Oct 06 2017
STATUS
approved

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Last modified April 25 06:35 EDT 2024. Contains 371964 sequences. (Running on oeis4.)