0,2

Mordechai Katzman, Knight's moves on an infinite board

a(n) = 28*n+8, n >= 4.

(1+5*x+12*x^2-8*x^4+4*x^5)*(1+x)/(1-x)^2;

Cf. A018836, A038522.

Sequence in context: A005879 A067519 A009245 this_sequence A139098 A130809 A018839

Adjacent sequences: A018839 A018840 A018841 this_sequence A018843 A018844 A018845

nonn,nice,walk,easy

njas, Marc LeBrun (mlb(AT)well.com)