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A027690 n^2 + n + 5. +0
3
5, 7, 11, 17, 25, 35, 47, 61, 77, 95, 115, 137, 161, 187, 215, 245, 277, 311, 347, 385, 425, 467, 511, 557, 605, 655, 707, 761, 817, 875, 935, 997, 1061, 1127, 1195, 1265, 1337, 1411, 1487, 1565, 1645, 1727, 1811, 1897, 1985, 2075, 2167, 2261 (list; graph; listen)
OFFSET

0,1

COMMENT

Except for the first term, a(n)=2*n+a(n-1), (with a(1)=7) [From Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Oct 23 2009]

LINKS

P. De Geest, Palindromic Quasi_Over_Squares of the form n^2+(n+X)

FORMULA

a(n)=2*n+a(n-1)-2 (with a(1)=5) [From Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Nov 07 2009]

EXAMPLE

For n=2, a(2)=2*2+5-2=7; n=3, a(3)=2*3+7-2=11; n=4, a(4)=2*4+11-2=17 [From Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Nov 07 2009]

MAPLE

with (combinat):seq(fibonacci(3, n)+n+4, n=0..47); - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Jun 07 2008

MATHEMATICA

Table[n^2+n+5, {n, 0, 100}] (T. D. Noe, Oct 29 2009)

CROSSREFS

Cf. A002522.

Sequence in context: A156104 A067830 A106862 this_sequence A087200 A153118 A145987

Adjacent sequences: A027687 A027688 A027689 this_sequence A027691 A027692 A027693

KEYWORD

nonn,new

AUTHOR

Patrick De Geest (pdg(AT)worldofnumbers.com)

EXTENSIONS

Corrected by T. D. Noe (noe(AT)sspectra.com), Nov 09 2006

Definition and offset fixed by Franklin T. Adams-Watters (FrankTAW(AT)Netscape.net), Jul 06 2009

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Last modified November 25 20:09 EST 2009. Contains 167514 sequences.


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