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A331772 a(n) = Sum_{-n<i<n, -n<j<n, gcd{i,j}=2} (n-|i|)*(n-|j|). 2
0, 0, 16, 48, 120, 224, 424, 688, 1096, 1600, 2392, 3344, 4568, 5984, 7976, 10256, 13112, 16320, 20360, 24848, 30136, 35936, 43208, 51152, 60184, 69952, 81800, 94576, 109000, 124448, 141944, 160592, 181480, 203648, 229400, 256688, 286424, 317792 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..38.

M. A. Alekseyev, M. Basova, and N. Yu. Zolotykh. On the minimal teaching sets of two-dimensional threshold functions. SIAM Journal on Discrete Mathematics 29:1 (2015), 157-165. doi:10.1137/140978090. See p. 158.

MAPLE

VR := proc(m, n, q) local a, i, j; a:=0;

for i from -m+1 to m-1 do for j from -n+1 to n-1 do

if gcd(i, j)=q then a:=a+(m-abs(i))*(n-abs(j)); fi; od: od: a; end;

[seq(VR(n, n, 2), n=1..50)];

CROSSREFS

When divided by 8 this becomes A331773.

Sequence in context: A023648 A098322 A175164 * A190112 A211576 A211590

Adjacent sequences:  A331769 A331770 A331771 * A331773 A331774 A331775

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Feb 08 2020

STATUS

approved

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Last modified October 5 23:01 EDT 2022. Contains 357261 sequences. (Running on oeis4.)