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A014642
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Even octagonal numbers: 4*n*(3*n-1).
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12
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0, 8, 40, 96, 176, 280, 408, 560, 736, 936, 1160, 1408, 1680, 1976, 2296, 2640, 3008, 3400, 3816, 4256, 4720, 5208, 5720, 6256, 6816, 7400, 8008, 8640, 9296, 9976, 10680, 11408, 12160, 12936, 13736, 14560, 15408, 16280, 17176, 18096, 19040, 20008, 21000, 22016
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,2
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COMMENTS
| 8 times pentagonal numbers. [From Omar E. Pol (info(AT)polprimos.com), Dec 11 2008]
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FORMULA
| a(n) = A000326(n)*8. [From Omar E. Pol (info(AT)polprimos.com), Dec 11 2008]
a(n) = A049450(n)*4 = A033579(n)*2. [From Omar E. Pol (info(AT)polprimos.com), Dec 13 2008]
a(n)=a(n-1)+24*n-16 (with a(0)=0) [From Vincenzo Librandi, Nov 20 2010]
G.f.: x*(8+16*x)/(1-3*x+3*x^2-x^3). [Colin Barker, Jan 06 2012]
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MATHEMATICA
| s=0; lst={s}; Do[s+=n++ +8; AppendTo[lst, s], {n, 0, 8!, 24}]; lst [From Vladimir Orlovsky (4vladimir(AT)gmail.com), Nov 16 2008]
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CROSSREFS
| Cf. A000567, A014641, A014793, A014794, A033579.
Cf. A000326. [From Omar E. Pol (info(AT)polprimos.com), Dec 11 2008]
Cf. A049450. [From Omar E. Pol (info(AT)polprimos.com), Dec 13 2008]
Sequence in context: A154425 A120931 A069083 * A143943 A135796 A105374
Adjacent sequences: A014639 A014640 A014641 * A014643 A014644 A014645
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KEYWORD
| nonn,easy
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AUTHOR
| Mohammad K. Azarian (ma3(AT)evansville.edu)
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EXTENSIONS
| More terms from Patrick De Geest (pdg(AT)worldofnumbers.com)
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