OFFSET
0,4
COMMENTS
The corresponding sum is in A168140.
The sequence contains negative numbers starting in row T(15,.) of the triangle.
EXAMPLE
As a triangle, sequence begins:
0;
1, 1;
5, 2, 5;
1, 5, 5, 1;
31, 29, 13, 29, 31;
1, 31, 14, 14, 31, 1;
...
MAPLE
T := proc(n, k) option remember; if k = 0 then (-1)^n*bernoulli(n) ; elif k > n/2 then procname(n, n-k) ; else procname(n-1, k-1)-procname(n, k-1) ; end if; end proc:
A085737 := proc(n, k) numer(T(n, k)) ; end proc:
A085738 := proc(n, k) denom(T(n, k)) ; end proc:
for n from 0 to 15 do for k from 0 to n do printf("%d, ", A085738(n, k)-A085737(n, k)) ; end do: end do: # R. J. Mathar, Mar 21 2010
PROG
(PARI) t(n, k) = if (k==0, (-1)^n*bernfrac(n), t(n-1, k-1) - t(n, k-1));
T(n, k) = my(tnk=t(n, k)); denominator(tnk) - numerator(tnk);
tabl(nn) = for (n=0, nn, for (k= 0, n, print1(T(n, k), ", ")); print); \\ Michel Marcus, Feb 01 2019
CROSSREFS
KEYWORD
sign,tabl
AUTHOR
Paul Curtz, Nov 26 2009
EXTENSIONS
Offset set to zero, sequence extended by R. J. Mathar, Mar 21 2010
Keywords sign and tabl from Michel Marcus, Feb 01 2019
STATUS
approved