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A100640 Triangle read by rows: numerators of Cotesian numbers C(n,k) (0 <= k <= n). 17

%I #15 Nov 12 2018 07:20:07

%S 0,1,1,1,2,1,1,3,3,1,7,16,2,16,7,19,25,25,25,25,19,41,9,9,34,9,9,41,

%T 751,3577,49,2989,2989,49,3577,751,989,2944,-464,5248,-454,5248,-464,

%U 2944,989,2857,15741,27,1209,2889,2889,1209,27,15741,2857,16067,26575,-16175,5675

%N Triangle read by rows: numerators of Cotesian numbers C(n,k) (0 <= k <= n).

%D Charles Jordan, Calculus of Finite Differences, Chelsea 1965, p. 513.

%D L. M. Milne-Thompson, Calculus of Finite Differences, MacMillan, 1951, p. 170.

%p (This defines the Cotesian numbers C(n,i)) with(combinat); C:=proc(n,i) if i=0 or i=n then RETURN( (1/n!)*add(n^a*stirling1(n,a)/(a+1),a=1..n+1) ); fi; (1/n!)*binomial(n,i)* add( add( n^(a+b)*stirling1(i,a)*stirling1(n-i,b)/((b+1)*binomial(a+b+1,b+1)), b=1..n-i+1), a=1..i+1); end;

%p # Another program:

%p T:=proc(n, k) (-1)^(n-k)*(n/(n-1))*binomial(n-1, k-1)* integrate(expand(binomial(t-1, n))/(t-k), t=1..n); end;

%p [[1], seq( [seq(T(n, k), k=1..n)], n=2..14)];

%t a[n_, i_] /; i == 0 || i == n = 1/n! Sum[n^a*StirlingS1[n, a]/(a + 1), {a, 1, n + 1}]; a[n_, i_] = 1/n!*Binomial[n, i]*Sum[ n^(a + b)*StirlingS1[i, a]*StirlingS1[n - i, b]/((b + 1)*Binomial[a + b + 1, b + 1]), {b, 1, n}, {a, 1, i + 1}]; Table[a[n, i], {n, 0, 10}, {i, 0, n}] // Flatten // Numerator // Take[#, 59]&

%t (* _Jean-François Alcover_, May 17 2011, after Maple prog. *)

%Y Cf. A100641-A100648, A100620, A100621, A002177, A002176.

%K sign,frac,tabl

%O 0,5

%A _N. J. A. Sloane_, Dec 04 2004

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Last modified April 25 09:15 EDT 2024. Contains 371967 sequences. (Running on oeis4.)