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A299919
Motzkin numbers (A001006) mod 4.
11
1, 1, 2, 0, 1, 1, 3, 3, 3, 3, 0, 2, 3, 3, 2, 0, 3, 3, 2, 0, 3, 3, 3, 3, 1, 1, 0, 2, 1, 1, 3, 3, 3, 3, 2, 0, 3, 3, 1, 1, 1, 1, 0, 2, 1, 1, 0, 2, 1, 1, 2, 0, 1, 1, 1, 1, 3, 3, 0, 2, 3, 3, 2, 0, 3, 3, 2, 0, 3, 3, 1, 1, 1, 1, 0, 2, 1, 1, 2, 0, 1, 1, 2, 0, 1
OFFSET
0,3
LINKS
MAPLE
f:= rectoproc({(3+3*n)*a(n)+(5+2*n)*a(1+n)+(-4-n)*a(n+2), a(0) = 1, a(1) = 1}, a(n), remember):
seq(f(n) mod 4, n=0..200); # Robert Israel, Mar 16 2018
MATHEMATICA
b = DifferenceRoot[Function[{b, n}, {3(n+1) b[n] + (2n+5) b[n+1] == (n+4) b[n+2], b[0] == 1, b[1] == 1}]];
a[n_] := Mod[b[n], 4];
Table[a[n], {n, 0, 100}] (* Jean-François Alcover, Feb 26 2019 *)
CROSSREFS
Motzkin numbers A001006 read mod 2,3,4,5,6,7,8,11: A039963, A039964, A299919, A258712, A299920, A258711, A299918, A258710.
Sequence in context: A246181 A123226 A347382 * A238270 A292521 A350828
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Mar 16 2018
STATUS
approved