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Search: id:A005892
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| A005892 |
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Truncated square numbers: 7*n^2 + 4*n + 1.
(Formerly M4833)
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+0
2
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| 1, 12, 37, 76, 129, 196, 277, 372, 481, 604, 741, 892, 1057, 1236, 1429, 1636, 1857, 2092, 2341, 2604, 2881, 3172, 3477, 3796, 4129, 4476, 4837, 5212, 5601, 6004, 6421, 6852, 7297, 7756, 8229, 8716, 9217, 9732, 10261, 10804, 11361, 11932
(list; graph; listen)
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OFFSET
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0,2
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REFERENCES
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N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
L. Hogben, Choice and Chance by Cardpack and Chessboard. Vol. 1, Chanticleer Press, NY, 1950, p. 36.
B. K. Teo and N. J. A. Sloane, Magic numbers in polygonal and polyhedral clusters, Inorgan. Chem. 24 (1985), 4545-4558.
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LINKS
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S. Plouffe, Approximations de S\'{e}ries G\'{e}n\'{e}ratrices et Quelques Conjectures, Dissertation, Universit\'{e} du Qu\'{e}bec \`{a} Montr\'{e}al, 1992.
S. Plouffe, 1031 Generating Functions and Conjectures, Universit\'{e} du Qu\'{e}bec \`{a} Montr\'{e}al, 1992.
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FORMULA
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a(n)=14*n+a(n-1)-17 (with a(1)=1) [From Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Nov 15 2009]
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EXAMPLE
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For n02, a(2)=14*2+1-17=12; n=3, a(3)=14*3+12-17=37; n=4, a(4)=14*4+37-17=76 [From Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Nov 15 2009]
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MAPLE
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A005892:=-(1+9*z+4*z**2)/(z-1)**3; [S. Plouffe in his 1992 dissertation.]
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CROSSREFS
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Cf. A135704.
Sequence in context: A045174 A044089 A044470 this_sequence A041276 A057457 A041278
Adjacent sequences: A005889 A005890 A005891 this_sequence A005893 A005894 A005895
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KEYWORD
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nonn,easy,new
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AUTHOR
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N. J. A. Sloane (njas(AT)research.att.com).
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EXTENSIONS
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More terms from Frank Ellermann, Jan 18 2002
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