0,2

T. D. Noe, Table of n, a(n) for n=0..1000

Index entries for crystal ball sequences

G.f.: [(1+2x)(1+2x+2x^2+2x^3-x^4)]/[(1-x)^3(1+x)^2]. - R. Stephan, Apr 24 2004

Adjacent sequences: A008577 A008578 A008579 this_sequence A008581 A008582 A008583

Sequence in context: A014813 A160420 A147411 this_sequence A123326 A025193 A002717

nonn,nice

N. J. A. Sloane (njas(AT)research.att.com).