A011543 Decimal expansion of e truncated to n places.

2, 27, 271, 2718, 27182, 271828, 2718281, 27182818, 271828182, 2718281828, 27182818284, 271828182845, 2718281828459, 27182818284590, 271828182845904, 2718281828459045, 27182818284590452, 271828182845904523, 2718281828459045235, 27182818284590452353, 271828182845904523536

Offset: 0

Author

N. J. A. Sloane

Keywords

• nonn
• easy
• base

Comments

a(n) <= A011544(n) <= a(n)+1. - Danny Rorabaugh, Mar 07 2015

Links

• Danny Rorabaugh, Table of n, a(n) for n = 0..999

Crossrefs

Cf. A001113, A011544.

Cf. A011545, A011547, A011549, A011551.

Programs

Mathematica

Module[{nn=30,edgs},edgs=RealDigits[E,10,nn][[1]];Table[ FromDigits[ Take[ edgs, n]],{n,nn}]] (* Harvey P. Dale, Oct 04 2017 *)

PARI

a(n) = floor(exp(1)*10^n); \\ Michel Marcus, Mar 08 2015

Python

from sympy import E
def a(n): return int(E*10**n)
print([a(n) for n in range(21)]) # Michael S. Branicky, Feb 27 2021

Formula

a(n) = floor(e*10^n).