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A229824 Even bisection gives sequence a itself, n->a(2*(9*n+k)-1) gives k-th differences of a for k=1..9 with a(n)=n for n<2.

%I A229824 #9 Mar 08 2017 04:26:14
%S A229824 0,1,1,-1,1,-1,-1,7,1,-21,-1,49,-1,-91,7,119,1,-57,-21,0,-1,-2,49,6,
%T A229824 -1,-14,-91,28,7,-42,119,28,1,62,-57,-236,-21,-2,0,4,-1,-8,-2,14,49,
%U A229824 -14,6,-14,-1,90,-14,-174,-91,96,28,2,7,-4,-42,6,119,0,28,-28,1
%N A229824 Even bisection gives sequence a itself, n->a(2*(9*n+k)-1) gives k-th differences of a for k=1..9 with a(n)=n for n<2.
%H A229824 Alois P. Heinz, <a href="/A229824/b229824.txt">Table of n, a(n) for n = 0..10000</a>
%F A229824 a(2*n) = a(n),
%F A229824 a(2*(9*n+k)-1) = Sum_{j=0..k} (-1)^j * C(k,j) * a(n+k-j) for k=1..9.
%p A229824 a:= proc(n) option remember; local m, q, r;
%p A229824       m:= (irem(n, 18, 'q')+1)/2;
%p A229824       `if`(n<2, n, `if`(irem(n, 2, 'r')=0, a(r),
%p A229824       add(a(q+m-j)*(-1)^j*binomial(m, j), j=0..m)))
%p A229824     end:
%p A229824 seq(a(n), n=0..100);
%t A229824 a[n_] := a[n] = Module[{m, q, r, q2, r2}, {q, r} = QuotientRemainder[n, 18]; m = (r+1)/2; If[n<2, n, {q2, r2} = QuotientRemainder[n, 2]; If[r2 == 0, a[q2], Sum[a[q+m-j]*(-1)^j*Binomial[m, j], {j, 0, m}]]]]; Table[a[n], {n, 0, 100}] (* _Jean-François Alcover_, Mar 08 2017, translated from Maple *)
%Y A229824 Cf. A005590, A229817, A229818, A229819, A229820, A229821, A229822, A229823, A229825.
%K A229824 sign,eigen
%O A229824 0,8
%A A229824 _Alois P. Heinz_, Sep 30 2013