A326303 - OEIS

%I #54 Oct 24 2019 11:34:45

%S 1,1,2,3,1,1,8,41,65,11,1,1,16,147,13247,907,109,73,1,1,128,8649,

%T 704707,1739,101717,3419,515,43,1,1,256,32307,660278641,6567221,

%U 4557449,29273,76667,15389,251,67,1,1,1024,487889,357852111131,54281321,15689290781,151587391,115560397,1659311,254977,34061,1733,289,1,1

%N Triangular array, read by rows: T(n,k) = numerator of Jtilde_k(n), 1 <= k <= 2*n+2.

%C When a general definition was made in a recent paper, it was slightly different from the previous definition. Please check the annotation on page 15 of the paper in 2019.

%H Seiichi Manyama, <a href="/A326303/b326303.txt">Rows n = 0..15, flattened</a>

%H Kazufumi Kimoto, Masato Wakayama, <a href="http://doi.org/10.2206/kyushujm.60.383">Apéry-like numbers arising from special values of spectral zeta functions for non-commutative harmonic oscillators</a>, Kyushu Journal of Mathematics, Vol. 60 (2006) No. 2 p. 383-404 (see Table 2).

%H Kazufumi Kimoto, Masato Wakayama, <a href="https://arxiv.org/abs/1905.01775">Apéry-like numbers for non-commutative harmonic oscillators and automorphic integrals</a>, arXiv:1905.01775 [math.PR], 2019. See p.22.

%F 4*n^2 * Jtilde_k(n) = (8*n^2 - 8*n + 3) * Jtilde_k(n-1) - 4*(n - 1)^2 * Jtilde_k(n-2) + 4 * Jtilde_{k - 2}(n-1).

%F Jtilde_n(2*n+1) = Jtilde_n(2*n+2) = 1/A001044(n). So T(n,2*n+1) = T(n,2*n+2) = 1.

%e Triangle begins:

%e       1,       1;

%e     2/3,     3/4,          1,       1;

%e    8/15,   41/64,      65/48,    11/8,     1/4,    1/4;

%e   16/35, 147/256, 13247/8640, 907/576, 109/216, 73/144, 1/36, 1/36;

%o (Ruby)

%o def f(n)

%o   return 1 if n < 2

%o   (1..n).inject(:*)

%o end

%o def Jtilde(k, n)

%o   return 0 if k == 0

%o   return (2r ** n * f(n)) ** 2 / f(2 * n + 1) if k == 1

%o   if n == 0

%o     return 1 if k == 2

%o     return 0

%o   end

%o   if n == 1

%o     return 3r / 4 if k == 2

%o     return 1      if k == 3 || k == 4

%o     return 0

%o   end

%o   ((8r * n * n - 8 * n + 3) * Jtilde(k, n - 1) - 4 * (n - 1) ** 2 * Jtilde(k, n - 2) + 4 * Jtilde(k - 2, n - 1)) / (4 * n * n)

%o end

%o def A326303(n)

%o   (0..n).map{|i| (1..2 * i + 2).map{|j| Jtilde(j, i).numerator}}.flatten

%o end

%o p A326303(10)

%Y Cf. A260832 (k=2), A264541 (k=3), A326748 (denominator).

%K nonn,frac,tabf

%O 0,3

%A _Seiichi Manyama_, Oct 19 2019