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A342467
a(n) is the number of n-th order magic triangles.
6
0, 4, 18, 700, 13123, 316424, 7317145, 176476738, 4279366371
OFFSET
2,2
COMMENTS
The Trotter reference gives the value 1356 = 76 * 18 for a(5), which is incorrect since 76 is the number of corner groupings and 18 is the maximum number of solutions in any grouping. - Andrew Howroyd, Feb 05 2022
LINKS
Andrew Howroyd, PARI Program, Feb 2022.
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.
FORMULA
a(n) < A351223(n). - Stefano Spezia, Feb 05 2022
PROG
(PARI) \\ See Links.
CROSSREFS
Row sums of A342384.
Sequence in context: A114574 A295223 A173222 * A367533 A156491 A287677
KEYWORD
nonn,more
AUTHOR
Stefano Spezia, Mar 13 2021
EXTENSIONS
a(5) corrected by Andrew Howroyd and Stefano Spezia, Feb 05 2022
a(6)-a(10) from Andrew Howroyd, Feb 05 2022
STATUS
approved