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A177071 (7n + 3)(7n + 4). 2
12, 110, 306, 600, 992, 1482, 2070, 2756, 3540, 4422, 5402, 6480, 7656, 8930, 10302, 11772, 13340, 15006, 16770, 18632, 20592, 22650, 24806, 27060, 29412, 31862, 34410, 37056, 39800, 42642, 45582, 48620, 51756, 54990, 58322, 61752, 65280 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

Cf. Zumkeller's contribution in A177059: in general, (h*n+h-k)*(h*n+k) = h^2*A002061(n+1)+(h-k)*k-h^2, therefore a(n) = 49*A002061(n+1)-37. - Bruno Berselli, Aug 24 2010

LINKS

Harvey P. Dale, Table of n, a(n) for n = 0..1000

Index entries for linear recurrences with constant coefficients, signature (3,-3,1).

FORMULA

a(n) = 98*n+a(n-1) with n>0, a(0)=12.

a(0)=12, a(1)=110, a(2)=306, a(n)=3*a(n-1)-3*a(n-2)+a(n-3) [From Harvey P. Dale, Oct 09 2011]

G.f.: -((2*(x+6)*(6*x+1))/(x-1)^3) [From Harvey P. Dale, Oct 09 2011]

MATHEMATICA

Table[(7n+3)(7n+4), {n, 0, 40}] (* or *) LinearRecurrence[{3, -3, 1}, {12, 110, 306}, 40] (* Harvey P. Dale, Oct 09 2011 *)

PROG

(PARI) a(n)=2*binomial(7*n+4, 2) \\ Charles R Greathouse IV, Jan 11 2012

CROSSREFS

Sequence in context: A081200 A016214 A037581 * A081183 A069294 A000559

Adjacent sequences:  A177068 A177069 A177070 * A177072 A177073 A177074

KEYWORD

nonn,easy

AUTHOR

Vincenzo Librandi, May 31 2010

EXTENSIONS

Edited by N. J. A. Sloane, Jun 22 2010

STATUS

approved

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Last modified September 28 11:24 EDT 2020. Contains 337393 sequences. (Running on oeis4.)