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A111146 Triangle T(n,k), read by rows, given by [0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, ...] DELTA [1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, ...] where DELTA is the operator defined in A084938. 13
1, 0, 1, 0, 0, 2, 0, 0, 1, 4, 0, 0, 2, 5, 8, 0, 0, 6, 15, 17, 16, 0, 0, 24, 62, 68, 49, 32, 0, 0, 120, 322, 359, 243, 129, 64, 0, 0, 720, 2004, 2308, 1553, 756, 321, 128, 0, 0, 5040, 14508, 17332, 11903, 5622, 2151, 769, 256, 0, 0, 40320, 119664 (list; table; graph; refs; listen; history; internal format)
OFFSET

0,6

COMMENTS

Let R(m,n,k), 0<=k<=n, the Riordan array (1, x*g(x)) where g(x) is g.f. of the m-fold factorials . Then Sum_{k, 0<=k<=n} = R(m,n,k) = Sum_{k, 0<=k<=n} T(n,k)*m^(n-k).

For m = -1, R(-1,n,k) is A026729(n,k).

For m = 0, R(0,n,k) is A097805(n,k).

For m = 1, R(1,n,k) is A084938(n,k).

For m = 2, R(2,n,k) is A111106(n,k).

FORMULA

Sum_{k, 0<=k<=n} (-1)^(n-k)*T(n, k) = A000045(n+1), Fibonacci numbers.

Sum_{k, 0<=k<=n} T(n, k) = A051295(n).

Sum_{k, 0<=k<=n} 2^(n-k)*T(n, k) = A112934(n).

T(0, 0) = 1, T(n, n) = 2^(n-1).

G.f.: A(x, y) = 1/(1 - x*y*Sum_{j>=0} (y-1+j)!/(y-1)!*x^j ). - Paul D. Hanna (pauldhanna(AT)juno.com), Oct 26 2005

EXAMPLE

Triangle begins:

.1;

.0, 1;

.0, 0, 2;

.0, 0, 1, 4;

.0, 0, 2, 5, 8;

.0, 0, 6, 15, 17, 16;

.0, 0, 24, 62, 68, 49, 32;

.0, 0, 120, 322, 359, 243, 129, 64;

.0, 0, 720, 2004, 2308, 1553, 756, 321, 128;

.0, 0, 5040, 14508, 17332, 11903, 5622, 2151, 769, 256;

.0, 0, 40320, 119664, 148232, 105048, 49840, 18066, 5756, 1793, 512;

....................................................................

At y=2: Sum_{k=0..n} 2^k*T(n,k) = A113327(n) where (1 + 2*x + 8*x^2 + 36*x^3 +...+ A113327(n)*x^n +..) = 1/(1 - 2/1!*x*(1! + 2!*x + 3!*x^2 + 4!*x^3 +..) ).

At y=3: Sum_{k=0..n} 3^k*T(n,k) = A113328(n) where (1 + 3*x + 18*x^2 + 117*x^3 +...+ A113328(n)*x^n +..) = 1/(1 - 3/2!*x*(2! + 3!*x + 4!*x^2 + 5!*x^3 +..) ).

At y=4: Sum_{k=0..n} 4^k*T(n,k) = A113329(n) where (1 + 4*x + 32*x^2 + 272*x^3 +...+ A113329(n)*x^n +..) = 1/(1 - 4/3!*x*(3! + 4!*x + 5!*x^2 + 6!*x^3 +..) ).

PROG

(PARI) {T(n, k)=local(x=X+X*O(X^n), y=Y+Y*O(Y^k)); A=1/(1-x*y*sum(j=0, n, x^j*prod(i=0, j-1, y+i))); return(polcoeff(polcoeff(A, n, X), k, Y))} (Hanna)

CROSSREFS

Cf. A000045, A026729, A051295, A084938, A097805, A111106, A112934.

Cf. m-fold factorials : A000142, A001147, A007559, A007696, A008548, A008542.

Cf. A113326, A113327 (y=2), A113328 (y=3), A113329 (y=4), A113330 (y=5), A113331 (y=6).

Sequence in context: A123634 A091866 A168511 * A109077 A137585 A072458

Adjacent sequences:  A111143 A111144 A111145 * A111147 A111148 A111149

KEYWORD

easy,nonn,tabl

AUTHOR

Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Oct 19 2005

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Last modified February 14 08:58 EST 2012. Contains 205614 sequences.