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A342384
Irregular triangle T read by rows: T(n, k) is the number of n-th order magic triangles with magic constant equal to A285009(n) + k, with 0 < k <= 3*n - 5.
2
0, 1, 1, 1, 1, 2, 0, 4, 6, 4, 0, 2, 18, 38, 71, 108, 115, 115, 108, 71, 38, 18, 155, 351, 695, 1067, 1475, 1815, 2007, 1815, 1475, 1067, 695, 351, 155, 1891, 4768, 9872, 15370, 22527, 30096, 35731, 37957, 37957, 35731, 30096, 22527, 15370, 9872, 4768, 1891
OFFSET
2,6
LINKS
Andrew Howroyd, Table of n, a(n) for n = 2..118 (rows 2..10)
Terrel Trotter, Normal Magic Triangles of Order n, Journal of Recreational Mathematics Vol. 5, No. 1, 1972, pp. 28-32.
Terrel Trotter, Perimeter-Magic Polygons, Journal of Recreational Mathematics Vol. 7, No. 1, 1974, pp. 14-20.
EXAMPLE
The triangle begins:
0;
1, 1, 1, 1;
2, 0, 4, 6, 4, 0, 2;
18, 38, 71, 108, 115, 115, 108, 71, 38, 18;
155, 351, 695, 1067, 1475, 1815, 2007, 1815, 1475, 1067, 695, 351, 155;
...
PROG
(PARI) \\ See A342467 for program code.
{ for(n=2, 6, print(A342384row(n))) } \\ Andrew Howroyd, Feb 05 2022
CROSSREFS
Cf. A016777 (row length), A179805, A285009, A341740, A342467 (row sums).
Sequence in context: A192133 A244109 A133144 * A192134 A322402 A196877
KEYWORD
nonn,tabf
AUTHOR
Stefano Spezia, Mar 10 2021
EXTENSIONS
Terms a(14) and beyond from Andrew Howroyd, Feb 05 2022
STATUS
approved