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The n-th differences of the row A141045(n,.).
1

%I #11 Dec 17 2014 06:24:17

%S -1,-2,-60,-120,-5040,-10080,-302400,-604800,-39916800,-79833600,

%T -217945728000,-435891456000,-2615348736000,-5230697472000,

%U -2667655710720000,-5335311421440000,-4257578514309120000,-8515157028618240000,-2810001819444019200000

%N The n-th differences of the row A141045(n,.).

%C Can be thought of as the second sequence of a family: the first is A091137, the third starts 1, 2, 84, 168.

%F a(n+1) = a(n)*A027760(n+3).

%e The first differences of A141045(2,.) are 11-(-19)=30 and -19-11 = -30. The 2nd difference is a(2)= -30-30= -60.

%t a[n_] := a[n] = a[n-1]*If[OddQ[n], 2, Denominator[BernoulliB[n+2]]]; a[0]=-1; Table[a[n], {n, 0, 18}] (* _Jean-François Alcover_, Dec 17 2014 *)

%o (PARI) a(n)=if(n,my(pr=a(n-1));fordiv(n+2,d,if(isprime(d+1),pr*=d+1));pr,-1) \\ _Charles R Greathouse IV_, Jul 08 2011

%K sign

%O 0,2

%A _Paul Curtz_, Aug 01 2008

%E Edited and extended by _R. J. Mathar_, Aug 12 2008