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A009759 Expansion of (3*x-17)/((x-1)*(x^2-6*x+1)). 0
-3, 0, 17, 116, 693, 4056, 23657, 137900, 803757, 4684656, 27304193, 159140516, 927538917, 5406093000, 31509019097, 183648021596, 1070379110493, 6238626641376, 36361380737777, 211929657785300, 1235216565974037 (list; graph; refs; listen; history; internal format)
OFFSET

0,1

COMMENTS

Numbers n such that 2*n^2 + 14*n + 25 is the square of an integer. - James Buddenhagen (jbuddenh(AT)gmail.com), Jul 19 2008

FORMULA

( (1+sqrt(2))^(2n-1) + (1-sqrt(2))^(2n-1) - 14 )/4.

a(n)-a(n-1)=A001541(n), n>0. [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Apr 23 2009]

CROSSREFS

A001652 - 3.

Sequence in context: A143779 A036968 A024040 * A127187 A057398 A013579

Adjacent sequences:  A009756 A009757 A009758 * A009760 A009761 A009762

KEYWORD

sign

AUTHOR

N. J. A. Sloane (njas(AT)research.att.com), Nick Baxter (nick(AT)visigenic.com)

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Last modified February 14 03:37 EST 2012. Contains 205570 sequences.