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Terms in A014217 pairwise swapped.
0

%I #3 Mar 30 2012 18:52:00

%S 1,1,4,2,11,6,29,17,76,46,199,122,521,321,1364,842,3571,2206,9349,

%T 5777,24476,15126,64079,39602,167761,103681,439204,271442,1149851,

%U 710646,3010349,1860497,7881196,4870846,20633239,12752042

%N Terms in A014217 pairwise swapped.

%C We can build an auxiliary b(n)=a(n+1)-2a(n) = -1,2,-6,7,..., its bisection b(2n)=a(2n+2)-2a(2n), then take the first differences b(2n+2)-b(2n) = a(2n+4)-3*a(2n+2)+2*a(2n) = -5, -10, -25, -65 and have obtained -A106729(n).

%F a(2n)=A014217(2n+1). a(2n+1)=A014217(2n).

%F a(n)=4*a(n-2)-4*(n-4)+a(n-6). G.f.: (1+x-2x^3-x^4+2x^5)/((1-x)(1+x)(x^2+x-1)(x^2-x-1)). [_R. J. Mathar_, Jan 23 2009]

%K nonn

%O 0,3

%A _Paul Curtz_, Jan 14 2009

%E Edited and extended by _R. J. Mathar_, Jan 23 2009