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A227608 Denominators of A225825(n) difference table written by antidiagonals.

%I A227608 #25 Sep 12 2013 03:14:43
%S A227608 1,2,2,6,3,6,2,3,3,2,30,15,15,15,30,2,15,15,15,15,2,42,21,105,105,105,
%T A227608 21,42,2,21,21,105,105,21,21,2,30,15,105,105,105,105,105,15,30,2,15,
%U A227608 15,105,105,105,105,15,15,2,66,33,165,165,1155,231,1155,165,165,33,66,2,33,33,165,165,231,231,165,165,33,33,2
%N A227608 Denominators of A225825(n) difference table written by antidiagonals.
%e A227608 1,
%e A227608 -1/2,      1/2,
%e A227608 -1/6,     -2/3,     -1/6,
%e A227608 1/2,       1/3,     -1/3,     -1/2,
%e A227608 7/30,    11/15,    16/15,    11/15,     7/30,
%e A227608 -3/2,   -19/15,    -8/15,     8/15,    19/15,    3/2,
%e A227608 -31/42, -47/21, -368/105, -424/105, -368/105, -47/21, -31/42.
%e A227608 Row sums: 1, 0/2, -6/6, 0/6, 90/30, 0/30, -3570/210, 0/210, 32550/210,... .
%e A227608 Are the denominators A034386(n+1)?
%e A227608 Reduced row sums: 1, 0, -1, 0, 3, 0, -17, 0, 155,... = -A036968(n+1)? See A226158(n+2). First 100 terms checked by Jean-François Alcover.
%t A227608 max = 12; b[0] = 1; b[n_] := Numerator[ BernoulliB[n, 1/2] - (n+1)*EulerE[n, 0]]; t = Table[b[n], {n, 0, max}] / Table[ Sum[ Boole[ PrimeQ[d+1]]/(d+1), {d, Divisors[n]}] // Denominator, {n, 0, max}]; dt = Table[ Differences[t, n], {n, 0, max}]; Table[ dt[[n-k+1, k]] // Denominator, {n, 1, max}, {k, 1, n}] // Flatten (* _Jean-François Alcover_, Aug 12 2013 *)
%Y A227608 Cf. A085738
%K A227608 nonn,frac,tabl
%O A227608 0,2
%A A227608 _Paul Curtz_, Aug 10 2013
%E A227608 More terms from _Jean-François Alcover_, Aug 12 2013