A108803 A108802 read mod 4.

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, 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, 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

Offset

1,2

Links

Table of n, a(n) for n=1..105.

Formula

a(n) = A000712(n-1)(mod 4). - John M. Campbell, Jul 16 2016

Maple

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

Mathematica

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 *)

Crossrefs

Sequence in context: A333451 A101664 A091952 * A348920 A348921 A050601

Adjacent sequences: A108800 A108801 A108802 * A108804 A108805 A108806

Keyword

nonn

Author

N. J. A. Sloane, Jul 09 2005

Extensions

More terms from R. J. Mathar, May 08 2007

Status

approved