A163168 - OEIS

%I #5 Nov 15 2016 02:42:26

%S 1,2,3,8,9,24,37,85,1115,29153,423233,2208087,5102497,9813637,

%T 15922076,19204759,106559540,120015709,1493877142,2199074984,

%U 32818755269,1505298832166,1507229768977,2841536357911,14805574584765

%N Pierce expansion of sech(1).

%C Pierce expansion of A073746.

%H G. C. Greubel, <a href="/A163168/b163168.txt">Table of n, a(n) for n = 1..1000</a>

%H Eric Weisstein, <a href="http://mathworld.wolfram.com/PierceExpansion.html">Pierce Expansion</a>, Mathworld.

%F 0.648054... = 1/1 - 1/(1*2) + 1/(1*2*3) - 1/(1*2*3*8) + 1/(1*2*3*8*9) - ...

%t PierceExp[A_, n_] := Join[Array[1 &, Floor[A]], First@Transpose@ NestList[{Floor[1/Expand[1 - #[[1]] #[[2]]]], Expand[1 - #[[1]] #[[2]]]} &, {Floor[1/(A - Floor[A])], A - Floor[A]}, n - 1]]; PierceExp[N[Sech[1] , 7!], 50] (* _G. C. Greubel_, Nov 14 2016 *)

%K nonn

%O 1,2

%A _R. J. Mathar_, Jul 22 2009