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 A099213 a(n) = a(n-1)+a(n-2)+3a(n-3), with a(0)=a(1)=a(2)=1. 3
 1, 1, 1, 5, 9, 17, 41, 85, 177, 385, 817, 1733, 3705, 7889, 16793, 35797, 76257, 162433, 346081, 737285, 1570665, 3346193, 7128713, 15186901, 32354193, 68927233, 146842129, 312831941, 666455769, 1419814097, 3024765689, 6443947093 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,4 COMMENTS Binomial transform is A099214. Binomial transform of A099212. LINKS FORMULA G.f.: (1-x^2)/(1-x-x^2-3x^2). PROG (Sage) from sage.combinat.sloane_functions import recur_gen3; it = recur_gen3(1, 1, 1, 1, 1, 3); [next(it) for i in range(32)] # Zerinvary Lajos, Jun 25 2008 CROSSREFS cf. A099212, A099214. Sequence in context: A147401 A062536 A324718 * A146067 A336139 A295627 Adjacent sequences:  A099210 A099211 A099212 * A099214 A099215 A099216 KEYWORD easy,nonn AUTHOR Paul Barry, Oct 06 2004 STATUS approved

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Last modified November 30 21:20 EST 2021. Contains 349426 sequences. (Running on oeis4.)