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A066714
Coordination sequence for ReO_3 net with respect to Re atom.
1
1, 6, 6, 30, 18, 78, 38, 150, 66, 246, 102, 366, 146, 510, 198, 678, 258, 870, 326, 1086, 402, 1326, 486, 1590, 578, 1878, 678, 2190, 786, 2526, 902, 2886, 1026, 3270, 1158, 3678, 1298, 4110, 1446, 4566, 1602, 5046, 1766, 5550, 1938, 6078, 2118, 6630, 2306
OFFSET
0,2
REFERENCES
Jean-Guillaume Eon (jgeon(AT)iq.ufrj.br), personal communication, Jan 05, 2002.
FORMULA
G.f.: (1+6*x+x^2)*(1+x^2)^2/(1-x^2)^3.
a(n) = 1 if n=1 or 2*n^2+5/2-(-1)^n*(n^2+1/2) if n>1. - C. Ronaldo (aga_new_ac(AT)hotmail.com), Dec 13 2004
MAPLE
1, seq(2*n^2+5/2-(-1)^n*(n^2+1/2), n=1..55); with(genfunc): seq(rgf_term((1+6*x+x^2)*(1+x^2)^2/(1-x^2)^3, x, i), i=0..55); # C. Ronaldo
CROSSREFS
Cf. A066394.
Sequence in context: A016725 A151779 A255462 * A054436 A055522 A078637
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Jan 19 2002
STATUS
approved