0,1

Northwest corner values of Ulam spiral with 101 at center.

Index entries for recurrences with constant coefficients

a(n)=3*a(n-1)-3*a(n-2)+a(n-3). G.f.: -(107-220*x+121*x^2)/(x-1)^3. [R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jul 24 2009]

Sequence in context: A156020 A160487 A096712 this_sequence A161372 A099652 A118774

Adjacent sequences: A161173 A161174 A161175 this_sequence A161177 A161178 A161179

nonn,easy

Milton L. Brown (miltbrown(AT)earthlink.net), Jun 05 2009, Jul 21 2009