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A153794
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4 times octagonal numbers: 4n(3n-2).
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2
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0, 4, 32, 84, 160, 260, 384, 532, 704, 900, 1120, 1364, 1632, 1924, 2240, 2580, 2944, 3332, 3744, 4180, 4640, 5124, 5632, 6164, 6720, 7300, 7904, 8532, 9184, 9860, 10560, 11284, 12032, 12804, 13600, 14420, 15264, 16132, 17024
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,2
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LINKS
| Index entries for sequences related to linear recurrences with constant coefficients, signature (3,-3,1).
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FORMULA
| a(n) = 12n^2 - 8n = A000567(n)*4 = A139267(n)*2.
a(n)=24*n+a(n-1)-20 (with a(0)=0) [From Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Aug 03 2010]
a(0)=0, a(1)=4, a(2)=32, a(n)=3*a(n-1)-3*a(n-2)+a(n-3) [From Harvey P. Dale, Jul 14 2011]
G.f.: -((4*(x+5*x^2))/(x-1)^3) [From Harvey P. Dale, Jul 14 2011]
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MATHEMATICA
| s=0; lst={s}; Do[s+=n; AppendTo[lst, s], {n, 4, 7!, 24}]; lst [From Vladimir Orlovsky (4vladimir(AT)gmail.com), Apr 02 2009]
Table[4n(3n-2), {n, 0, 40}] (* or *) LinearRecurrence[{3, -3, 1}, {0, 4, 32}, 41] (* From Harvey P. Dale, Jul 14 2011 *)
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CROSSREFS
| Cf. A000567, A139267, A152751, A153808.
Sequence in context: A138340 A113250 A012036 * A108914 A052469 A033430
Adjacent sequences: A153791 A153792 A153793 * A153795 A153796 A153797
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KEYWORD
| easy,nonn
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AUTHOR
| Omar E. Pol (info(AT)polprimos.com), Jan 19 2009
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