login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

Triangle read by rows. T(n, k) = [x^k](0^n + 4^n * ((2 - 2*(1 - x)^(1/2)) / x - 1)).
1

%I #4 Sep 09 2022 04:05:45

%S 1,0,1,0,4,2,0,16,8,5,0,64,32,20,14,0,256,128,80,56,42,0,1024,512,320,

%T 224,168,132,0,4096,2048,1280,896,672,528,429,0,16384,8192,5120,3584,

%U 2688,2112,1716,1430,0,65536,32768,20480,14336,10752,8448,6864,5720,4862

%N Triangle read by rows. T(n, k) = [x^k](0^n + 4^n * ((2 - 2*(1 - x)^(1/2)) / x - 1)).

%F T(n, 0) = 0^n, T(n, n) = CatalanNumber(n), otherwise T(n, k) = 4^(n - k)*T(k, k).

%e [0] 1;

%e [1] 0, 1;

%e [2] 0, 4, 2;

%e [3] 0, 16, 8, 5;

%e [4] 0, 64, 32, 20, 14;

%e [5] 0, 256, 128, 80, 56, 42;

%e [6] 0, 1024, 512, 320, 224, 168, 132;

%e [7] 0, 4096, 2048, 1280, 896, 672, 528, 429;

%e [8] 0, 16384, 8192, 5120, 3584, 2688, 2112, 1716, 1430;

%e [9] 0, 65536, 32768, 20480, 14336, 10752, 8448, 6864, 5720, 4862;

%p ogf := n -> 0^n + 4^n * ((2 - 2*(1 - x)^(1/2)) / x - 1):

%p ser := n -> series(ogf(n), x, 32):

%p seq(lprint([n], seq(coeff(ser(n), x, k), k = 0..n)), n = 0..9);

%Y Cf. A000108, A000302, A008549 (row sums), A356651.

%K nonn,tabl

%O 0,5

%A _Peter Luschny_, Sep 09 2022