OFFSET
0,5
COMMENTS
This is row i=0 of an array defined as T(i,j) = (-1)^(i+j+1)*A091137(j)*a(i,j), columns j >= 0, which starts
-1, 1, 1, 1, 19, 27, 863, ...
1, -3, 5, 1, 11, 11, 271, ...
-1, 5, -23, 9, 19, 11, 191, ...
1, -7, 53, -55, 251, 27, 271, ...
-1, 9, -95, 161, -1901, 475, 863, ...
1, -11, 149, -351, 6731, -4277, 19087, ...
...
The first two rows are related via T(0,j) = A027760(j)*T(0,j-1) - T(1,j).
REFERENCES
P. Curtz, Integration .., note 12, C.C.S.A., Arcueil, 1969.
FORMULA
a(i,j) = a(i-1,j) + a(i-1,j-1), see reference page 33.
(q+1-j)*Sum_{j=0..q} a(i,j)*(-1)^(q-j) = binomial(i,q), see reference page 35.
a(n) = numerator(n*(n+1)*Sum_{k=1..n} ((-1)^(n-k)*Stirling2(n+k,k)*binomial(2*n-1,n-k))/((n+k)*(n+k-1))), n>0, a(0)=-1. - Vladimir Kruchinin, Dec 12 2016
MAPLE
A091137 := proc(n) local a, i, p ; a := 1 ; for i from 1 do p := ithprime(i) ; if p > n+1 then break; fi; a := a*p^floor(n/(p-1)) ; od: a ; end proc:
A048994 := proc(n, k) combinat[stirling1](n, k) ; end proc:
a := proc(i, j) add(A048994(j, k)*x^k, k=0..j) ; int(%, x=i..i+1) ; %/j! ; end proc:
seq(A141417(n), n=0..40) ; # R. J. Mathar, Nov 17 2010
MATHEMATICA
(* a7 = A091137 *) a7[n_] := a7[n] = Times @@ Select[ Divisors[n]+1, PrimeQ]*a7[n-1]; a7[0]=1; a[n_] := (-1)^(n+1) * a7[n] * Integrate[ (-1)^n*Pochhammer[-x, n], {x, 0, 1}]/n!; Table[a[n], {n, 0, 10}] (* Jean-François Alcover, Aug 10 2012 *)
PROG
(Maxima)
a(n):=if n=0 then -1 else num(n*(n+1)*sum(((-1)^(n-k)*stirling2(n+k, k)*binomial(2*n-1, n-k))/((n+k)*(n+k-1)), k, 1, n)); /* Vladimir Kruchinin, Dec 12 2016 */
CROSSREFS
KEYWORD
sign
AUTHOR
Paul Curtz, Aug 05 2008
EXTENSIONS
Erroneous formula linking A091137 and A002196 removed, and more terms and program added by R. J. Mathar, Nov 17 2010
STATUS
approved