A332365 Triangle read by rows: T(m,n) = number of threshold functions (the function u_{0,2}(m,n) of Alekseyev et al. 2015) for m >= n >= 2.

3, 6, 13, 9, 21, 33, 12, 30, 49, 73, 15, 40, 66, 99, 133, 18, 51, 85, 130, 177, 237, 21, 63, 106, 164, 224, 301, 381, 24, 76, 130, 202, 277, 374, 475, 593, 27, 90, 154, 241, 331, 448, 570, 713, 857, 30, 105, 182, 287, 395, 538, 687, 862, 1039, 1261, 33, 121, 211, 335, 462, 632, 808, 1016, 1226, 1489, 1757

Offset

2,1

Links

Table of n, a(n) for n=2..67.

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 Theorem 11.

Example

Triangle begins:
3,
6, 13,
9, 21, 33,
12, 30, 49, 73,
15, 40, 66, 99, 133,
18, 51, 85, 130, 177, 237,
21, 63, 106, 164, 224, 301, 381,
24, 76, 130, 202, 277, 374, 475, 593,
27, 90, 154, 241, 331, 448, 570, 713, 857,
...

Maple

VQ := proc(m, n, q) local eps, a, i, j; eps := 10^(-6); a:=0;
for i from ceil(-m+eps) to floor(m-eps) do
for j from ceil(-n+eps) to floor(n-eps) do
if gcd(i, j)=q then a:=a+(m-abs(i))*(n-abs(j)); fi; od: od: a; end;
VS := proc(m, n) local a, i, j; a:=0;
for i from 1 to m-1 do for j from 1 to n-1 do
if gcd(i, j)=1 then a:=a+1; fi; od: od: a; end; # A331781
u02:=(m, n) -> VQ(m, n, 2)+2-2*VQ(m/2, n/2, 1)+VS(m, n); # This sequence
for m from 2 to 12 do lprint([seq(u02(m, n), n=2..m)]); od:

Crossrefs

Cf. A332350, A332352, A332363, A331781.

Main diagonal is A332366.

Sequence in context: A009788 A102966 A309719 * A257276 A248043 A189420

Adjacent sequences: A332362 A332363 A332364 * A332366 A332367 A332368

Keyword

nonn,tabl

Author

N. J. A. Sloane, Feb 11 2020

Status

approved