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A038716 a(n) = floor(n/4)*ceiling((n+3)/4). 1
0, 0, 0, 0, 2, 2, 3, 3, 6, 6, 8, 8, 12, 12, 15, 15, 20, 20, 24, 24, 30, 30, 35, 35, 42, 42, 48, 48, 56, 56, 63, 63, 72, 72, 80, 80, 90, 90, 99, 99, 110, 110, 120, 120, 132, 132, 143, 143, 156, 156, 168, 168, 182, 182, 195, 195, 210, 210, 224, 224, 240 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,5

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..10000

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

FORMULA

a(n) = a(n-1) +a(n-2) -a(n-3) +a(n-4) -a(n-5) -a(n-6) +a(n-7). - R. J. Mathar, Mar 11 2012

MAPLE

A038716:=n->floor(n/4)*ceil((n+3)/4): seq(A038716(n), n=0..100); # Wesley Ivan Hurt, Jan 03 2017

MATHEMATICA

Table[Floor[n/4]Ceiling[(n+3)/4], {n, 0, 70}] (* Harvey P. Dale, Sep 19 2011 *)

PROG

(MAGMA) [Floor(n/4)*Ceiling((n+3)/4): n in [0..60]]; // Vincenzo Librandi, Sep 21 2011

CROSSREFS

Sequence in context: A101081 A147795 A258186 * A168659 A035642 A213332

Adjacent sequences:  A038713 A038714 A038715 * A038717 A038718 A038719

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane, May 02 2000

STATUS

approved

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Last modified September 16 23:53 EDT 2021. Contains 347477 sequences. (Running on oeis4.)