A064748 a(n) = n*10^n + 1.

1, 11, 201, 3001, 40001, 500001, 6000001, 70000001, 800000001, 9000000001, 100000000001, 1100000000001, 12000000000001, 130000000000001, 1400000000000001, 15000000000000001, 160000000000000001, 1700000000000000001, 18000000000000000001

Offset

0,2

Comments

Number of digits in (10^n)^(10^n) in base 10. - Altug Alkan, Apr 25 2016

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..1000

Paul Leyland, Cullen and Woodall numbers and their generalization to other bases

Formula

From Ilya Gutkovskiy, Apr 25 2016: (Start)

O.g.f.: (1 - 10*x + 90*x^2)/((1 - x)*(1 - 10*x)^2).

E.g.f.: (1 + 10*x*exp(9*x))*exp(x). (End)

Mathematica

Table[n 10^n + 1, {n, 0, 18}] (* Michael De Vlieger, Apr 25 2016 *)

Prog

(Magma) [ n*10^n+1: n in [0..20]]; // Vincenzo Librandi, Sep 16 2011
(PARI) a(n) = n*10^n + 1; \\ Altug Alkan, Apr 25 2016

Crossrefs

Sequence in context: A352842 A268959 A213531 * A191556 A091814 A280957

Adjacent sequences: A064745 A064746 A064747 * A064749 A064750 A064751

Keyword

easy,nonn

Author

N. J. A. Sloane, Oct 19 2001

Status

approved