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A108802 read mod 4.
3

%I #13 Jul 28 2016 21:55:04

%S 1,2,1,2,0,0,1,2,1,0,1,0,1,2,1,0,2,2,2,2,2,2,2,2,3,0,3,0,3,2,0,2,1,2,

%T 1,2,1,2,2,2,3,0,0,2,0,2,1,2,3,0,0,0,0,2,2,0,0,2,1,2,2,0,0,2,3,0,1,0,

%U 2,0,1,0,1,0,3,2,1,0,1,0,2,2,1,2,0,0,1,2,3,0,0,2,0,2,2,0,3,0,1,0,2,2,3,0,1

%N A108802 read mod 4.

%F a(n) = A000712(n-1)(mod 4). - _John M. Campbell_, Jul 16 2016

%p A000041 := proc(n) combinat[numbpart](n) ; end: A040051 := proc(n) option remember ; A000041(n) mod 2 ; end: A108802 := proc(n) option remember ; add( A040051(i)*A040051(n-i-1),i=0..n-1) ; end: A108803 := proc(n) A108802(n) mod 4 ; end: for n from 1 to 140 do printf("%d, ",A108803(n)) ; od ; # _R. J. Mathar_, May 08 2007

%t Function[w, Mod[ListConvolve[#, #], 4] & /@ Map[Take[w, #] &, Range@ Length@ w]]@ Table[Mod[PartitionsP@ n, 2], {n, 0, 105}] // Flatten (* _Michael De Vlieger_, Jul 16 2016 *)

%K nonn

%O 1,2

%A _N. J. A. Sloane_, Jul 09 2005

%E More terms from _R. J. Mathar_, May 08 2007