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A038715 Floor(n/4)*ceiling((n+2)/4). 0
0, 0, 0, 0, 2, 2, 2, 3, 6, 6, 6, 8, 12, 12, 12, 15, 20, 20, 20, 24, 30, 30, 30, 35, 42, 42, 42, 48, 56, 56, 56, 63, 72, 72, 72, 80, 90, 90, 90, 99, 110, 110, 110, 120, 132, 132, 132, 143, 156, 156, 156, 168, 182, 182, 182, 195, 210, 210, 210, 224, 240 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,5

LINKS

Table of n, a(n) for n=0..60.

Index entries for linear recurrences with constant coefficients, signature (2,-2,2,0,-2,2,-2,1).

FORMULA

a(n) = +2 a(n-1) -2 a(n-2) +2 a(n-3) -2 a(n-5) +2 a(n-6) -2 a(n-7) +a(n-8). - R. J. Mathar, Mar 11 2012

MATHEMATICA

LinearRecurrence[{2, -2, 2, 0, -2, 2, -2, 1}, {0, 0, 0, 0, 2, 2, 2, 3}, 80] (* Harvey P. Dale, Nov 05 2014 *)

CROSSREFS

Sequence in context: A104856 A306393 A324763 * A293518 A057040 A096235

Adjacent sequences:  A038712 A038713 A038714 * A038716 A038717 A038718

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, May 02 2000

STATUS

approved

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Last modified March 21 22:19 EDT 2019. Contains 321382 sequences. (Running on oeis4.)