A260677 a(n) = number of decimal digits in the n-th odd Catalan number A038003(n).

1, 1, 1, 3, 7, 17, 35, 74, 150, 304, 612, 1228, 2460, 4926, 9857, 19721, 39449, 78905, 157818, 315644, 631296, 1262601, 2525212, 5050435, 10100879, 20201769, 40403550, 80807112, 161614235, 323228483, 646456979, 1292913972, 2585827958, 5171655931, 10343311876

Offset

0,4

Links

Jon E. Schoenfield, Table of n, a(n) for n = 0..1000

Mathematica

Table[Floor[Log[CatalanNumber[2^n - 1]]/Log[10]] + 1, {n, 0, 27}]
f[n_] := Floor[(LogGamma[2^(n + 1) - 1] - 2*LogGamma[2^n] - n*Log[2])/Log[10]] + 1; Array[f, 34, 0] (* Robert G. Wilson v, Nov 21 2015 *)

Prog

(Magma) [Floor((LogGamma(2^(j+1)-1)-2*LogGamma(2^j)-Log(2^j))/Log(10))+1: j in [0..34]]; // Jon E. Schoenfield, Nov 21 2015
(Magma) [Floor(Log(Catalan(2^n-1))/Log(10)) + 1: n in [0..20]]; // Vincenzo Librandi, Nov 22 2015

Crossrefs

Cf. A000108, A038003.

Sequence in context: A178521 A034482 A114100 * A014395 A326520 A295146

Adjacent sequences: A260674 A260675 A260676 * A260678 A260679 A260680

Keyword

nonn,base

Author

L. Edson Jeffery, Nov 15 2015

Extensions

a(28)-a(34) from Jon E. Schoenfield, Nov 21 2015

Status

approved