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A046162 Reduced numerators of (n-1)^2/(n^2+n+1). Arises in Routh's theorem. 2
0, 1, 4, 3, 16, 25, 12, 49, 64, 27, 100, 121, 48, 169, 196, 75, 256, 289, 108, 361, 400, 147, 484, 529, 192, 625, 676, 243, 784, 841, 300, 961, 1024, 363, 1156, 1225, 432, 1369, 1444, 507, 1600, 1681, 588, 1849, 1936, 675, 2116, 2209, 768, 2401, 2500 (list; graph; refs; listen; history; internal format)
OFFSET

1,3

COMMENTS

Multiplicative with a(3^e) = 3^(2e-1), p^(2e) otherwise. David W. Wilson (davidwwilson(AT)comcast.net) Jun 12, 2005.

LINKS

Eric Weisstein's World of Mathematics, Link to a section of The World of Mathematics.

FORMULA

G.f.: x(x^8+4x^7+3x^6+13x^5+13x^4+3x^3+4x^2+x)/(1-x^3)^3.

a(n) = n^2/3 == 0 mod 3, n^2 otherwise. David W. Wilson (davidwwilson(AT)comcast.net) Jun 12, 2005.

MAPLE

seq(numer((n-1)^2/(n^2+n+1)), n=1..51) ; - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Jun 04 2008

seq(denom(3/n^2-2), n=0..76) ; - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Jun 04 2008

CROSSREFS

Cf. A046163.

Sequence in context: A058557 A038233 A176737 * A060509 A113203 A034486

Adjacent sequences:  A046159 A046160 A046161 * A046163 A046164 A046165

KEYWORD

nonn,mult

AUTHOR

Eric Weisstein (eric(AT)weisstein.com)

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Last modified February 16 14:37 EST 2012. Contains 205930 sequences.