A381295 a(n) = numerator( [(x*y*z*u*v)^n] 1/sqrt(1 - (x + y + z + u + v*(x*y*z + x*y*u + x*z*u + y*z*u))) ).

1, 3, 735, 1155, 152927775, 5729606883, 944642139441, 20804764619925, 31532612849128108575, 1514216480447305259625, 1198479499879816971151335, 15183210867901962855773895, 200941692389810767447918272225, 10564290945275296828332253777425, 4507504507128763568843859426010875

Offset

0,2

Links

Table of n, a(n) for n=0..14.

S. Hassani, J.-M. Maillard, and N. Zenine, On the diagonals of rational functions: the minimal number of variables (unabridged version), arXiv:2502.05543 [math-ph], 2025. See p. 44.

Mathematica

a[n_]:=Numerator[SeriesCoefficient[1/Sqrt[1-(x+y+z+u+v(x*y*z+x*y*u+x*z*u+y*z*u))], {x, 0, n}, {y, 0, n}, {z, 0, n}, {u, 0, n}, {v, 0, n}]]; Array[a, 15, 0]

Crossrefs

Cf. A381296 (denominator).

Sequence in context: A013826 A255012 A133014 * A100407 A332173 A119264

Adjacent sequences: A381292 A381293 A381294 * A381296 A381297 A381298

Keyword

nonn,frac

Author

Stefano Spezia, Feb 19 2025

Status

approved