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 A055372 Invert transform of Pascal's triangle A007318. 10
 1, 1, 1, 2, 4, 2, 4, 12, 12, 4, 8, 32, 48, 32, 8, 16, 80, 160, 160, 80, 16, 32, 192, 480, 640, 480, 192, 32, 64, 448, 1344, 2240, 2240, 1344, 448, 64, 128, 1024, 3584, 7168, 8960, 7168, 3584, 1024, 128, 256, 2304, 9216, 21504, 32256, 32256, 21504, 9216 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 0,4 COMMENTS Triangle T(n,k), 0<=k<=n, read by rows, given by [1, 1, 0, 0, 0, 0, 0, 0, 0, ...] DELTA [1, 1, 0, 0, 0, 0, 0, 0, 0, ...] where DELTA is the operator defined in A084938 . - Philippe Deléham (kolotoko(aT)lagoon.nc), Aug 10 2005 T(n,k) is the number of nonempty bit strings with n bits and exactly k 1's over all strings in the sequence.  For example T(2,1) =4 because we have: {(01)},{(10)},{(0),(1)},{(1),(0)}. - Geoffrey Critzer, Apr 06 2013 LINKS N. J. A. Sloane, Transforms FORMULA a(n, k)=2^(n-1)*C(n, k). G.f.: A(x, y)=(1-x-xy)/(1-2x-2xy). As an infinite lower triangular matrix, equals A134309 * A007318. - Gary W. Adamson, Oct 19 2007 Sum_{k, 0<=k<=n} T(n,k)*x^k = A000007(n), A011782(n), A081294(n), A081341(n), A092811(n), A093143(n), A067419(n) for x = -1, 0, 1, 2, 3, 4, 5 respectively. - Philippe Deléham, Feb 05 2012 EXAMPLE 1; 1,1; 2,4,2; 4,12,12,4; 8,32,48,32,8; ... MATHEMATICA nn=10; f[list_]:=Select[list, #>0&]; a=(x+y x)/(1-(x+y x)); Map[f, CoefficientList[Series[1/(1-a), {x, 0, nn}], {x, y}]]//Grid  (* Geoffrey Critzer, Apr 06 2013 *) CROSSREFS Row sums give A081294. Cf. A000079, A007318, A055373, A055374. Cf. A134309. Sequence in context: A240893 A241108 A151706 * A241078 A198285 A136620 Adjacent sequences:  A055369 A055370 A055371 * A055373 A055374 A055375 KEYWORD nonn,tabl AUTHOR Christian G. Bower, May 16 2000 STATUS approved

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Last modified December 15 11:52 EST 2018. Contains 318148 sequences. (Running on oeis4.)