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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A262706 Triangle: Newton expansion of C(n,m)^5, read by rows.

Original entry on oeis.org

1, 0, 1, 0, 30, 1, 0, 150, 240, 1, 0, 240, 6810, 1020, 1, 0, 120, 63540, 94890, 3120, 1, 0, 0, 271170, 2615340, 740640, 7770, 1, 0, 0, 604800, 32186070, 47271840, 4029690, 16800, 1, 0, 0, 730800, 214628400, 1281612570, 518276640, 17075940, 32760, 1, 0, 0, 453600, 859992000, 18459063000, 26947757970, 4027831080, 60171300, 59040, 1
Offset: 0

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Author

Giuliano Cabrele, Sep 30 2015

Keywords

Comments

Triangle here T_5(n,m) is such that C(n,m)^5 = Sum_{j=0..n} C(n,j)*T_5(j,m).
Equivalently, lower triangular matrix T_5 such that
|| C(n,m)^5 || = P * T_5 = A007318 * T_5.
T_5(n,m) = 0 for n < m and for 5*m < n.
Refer to comment to A262704.
Example:
C(x,2)^5 = x^5*(x-1)^5/32 = 1*C(x,2) + 240*C(x,3) + 6810*C(x,4) + 63540*C(x,5) + 271170*C(x,6) + 604800*C(x,7) + 730800*C(x,8) + 453600*C(x,9) + 113400*C(x,10);
C(5,2)^5 = C(5,3)^5 = 100000 = 1*C(5,2) + 240*C(5,3) + 6810*C(5,4) + 63540*C(5,5) = 1*C(5,3) + 1020*C(5,4) + 94890*C(5,5).

Examples

			Triangle starts:
[1];
[0,   1];
[0,  30,      1];
[0, 150,    240,       1];
[0, 240,   6810,    1020,      1];
[0, 120,  63540,   94890,   3120,    1];
[0,   0, 271170, 2615340, 740640, 7770, 1];
		

Crossrefs

Second diagonal (T_5(n+1,n)) is A061167(n+1).
Column T_5(n,2) is A122193(5,n).
Cf. A109983 (transpose of), A262704, A262705.

Programs

  • Magma
    [&+[(-1)^(n-j)*Binomial(n,j)*Binomial(j,m)^5: j in [0..n]]: m in [0..n], n in [0..10]]; // Bruno Berselli, Oct 01 2015
    
  • Mathematica
    T5[n_, m_] := Sum[(-1)^(n - j) * Binomial[n, j] * Binomial[j, m]^5, {j, 0, n}]; Table[T5[n, m], {n, 0, 9}, {m, 0, n}] // Flatten (* Jean-François Alcover, Oct 01 2015 *)
  • MuPAD
    // as a function
    T_5:=(n,m)->_plus((-1)^(n-j)*binomial(n,j)*binomial(j,m)^5 $ j=0..n):
    // as a matrix h x h
    _P:=h->matrix([[binomial(n,m) $m=0..h]$n=0..h]):
    _P_5:=h->matrix([[binomial(n,m)^5 $m=0..h]$n=0..h]):
    _T_5:=h->_P(h)^-1*_P_5(h):
    
  • PARI
    T_5(nmax) = {for(n=0, nmax, for(m=0, n, print1(sum(j=0, n, (-1)^(n-j)*binomial(n,j)*binomial(j,m)^5), ", ")); print())} \\ Colin Barker, Oct 01 2015

Formula

T_5(n,m) = Sum_{j=0..n} (-1)^(n-j)*C(n,j)*C(j,m)^5.
Also, let S(r,s)(n,m) denote the Generalized Stirling2 numbers as defined in the link above, then T_5(n,m) = n! / (m!)^5 * S(m,m)(5,n).