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A048507 a(n) = T(2,n), array T given by A048505. 3
1, 10, 35, 101, 269, 685, 1693, 4093, 9725, 22781, 52733, 120829, 274429, 618493, 1384445, 3080189, 6815741, 15007741, 32899069, 71827453, 156237821, 338690045, 731906045, 1577058301, 3388997629, 7264534525, 15535702013, 33151778813, 70598524925 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

n-th difference of a(n), a(n-1), ..., a(0) is (9, 16, 25, 36, 49, ...).

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..2000

Index entries for linear recurrences with constant coefficients, signature (7,-18,20,-8).

FORMULA

a(n) = (n^2+9*n+16) * 2^(n-2) - 3. - Ralf Stephan, Feb 05 2004

a(n) = 7*a(n-1)-18*a(n-2)+20*a(n-3)-8*a(n-4). - Colin Barker, Nov 27 2014

G.f.: (16*x^3-17*x^2+3*x+1) / ((x-1)*(2*x-1)^3). - Colin Barker, Nov 27 2014

PROG

(MAGMA) [(n^2+9*n+16) * 2^(n-2) - 3: n in [0..30]]; // Vincenzo Librandi, Sep 26 2011

(PARI) Vec((16*x^3-17*x^2+3*x+1)/((x-1)*(2*x-1)^3) + O(x^100)) \\ Colin Barker, Nov 27 2014

CROSSREFS

Sequence in context: A272352 A309883 A049736 * A240267 A221907 A195269

Adjacent sequences:  A048504 A048505 A048506 * A048508 A048509 A048510

KEYWORD

nonn,easy

AUTHOR

Clark Kimberling

STATUS

approved

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Last modified February 28 23:19 EST 2020. Contains 332353 sequences. (Running on oeis4.)