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A132209 Sequence gives X values from solving the equation 2*X^3 + 3*X^2 = Y^2. 7
0, 3, 11, 23, 39, 59, 83, 111, 143, 179, 219, 263, 311, 363, 419, 479, 543, 611, 683, 759, 839, 923, 1011, 1103, 1199, 1299, 1403, 1511, 1623, 1739, 1859, 1983, 2111, 2243, 2379, 2519, 2663, 2811, 2963, 3119 (list; graph; refs; listen; history; internal format)
OFFSET

0,2

COMMENTS

Essentially identical to A142463.

To find Y values: b(n)=(2*n^2 + 2n - 1)(2n - 1).

FORMULA

a(n)=2*n^2 + 2n - 1, with n>=1.

G.f.: x*(1+x)*(3-x)/(1-x)^3. - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Nov 14 2007

MATHEMATICA

f[n_]:=Inner[Times, {n, n+1}, {n+2, n+3}, Plus]; Table[f[n], {n, 0, 5!}] [From Vladimir Orlovsky (4vladimir(AT)gmail.com), Feb 08 2010]

CROSSREFS

Cf. A005563, A046092, A001082, A002378, A036666, A062717, A028347, A087475, A000217.

Cf. A153238 [From Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Jan 03 2009]

Sequence in context: A072671 A119173 A106201 * A142463 A086497 A121509

Adjacent sequences:  A132206 A132207 A132208 * A132210 A132211 A132212

KEYWORD

nonn

AUTHOR

Mohamed Bouhamida (bhmd95(AT)yahoo.fr), Nov 06 2007

EXTENSIONS

Edited by the Associate Editors of the OEIS, Nov 15 2009

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Last modified February 16 01:56 EST 2012. Contains 205860 sequences.