A099969 - OEIS

A099969

Write 1/e as a binary fraction; read this from left to right and whenever a 1 appears, note the integer formed by reading leftwards from that 1.

2, 10, 26, 58, 122, 1146, 5242, 13434, 46202, 177274, 701562, 1750138, 18527354, 52081786, 186299514, 454734970, 4749702266, 21929571450, 56289309818, 331167216762, 880923030650, 1980434658426, 6378481169530, 15174574191738

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,1

LINKS

Table of n, a(n) for n=0..23.

EXAMPLE

1/e = 0.367879441171442321595523770161460867445811131031767834507... = 0.010111100010110101011000110110001011001110111100110111110001101010111010110111 in binary.

From the binary expansion we get 10 = 2, 1010 = 10, 11010 = 26, 111010 = 58, 1111010 = 122, etc.

MATHEMATICA

d = 100; l = First[RealDigits[N[1/E, d], 2]]; Do[m = Take[l, n]; k = Length[m]; If[m[[k]] == 1, Print[2*FromDigits[Reverse[m], 2]]], {n, 1, d}] (* Ryan Propper, Aug 18 2005 *)

CROSSREFS

Cf. A068985, A099970, A099971, A099972, A099973, A099974.

Sequence in context: A277712 A009307 A131130 * A241688 A183331 A324914

Adjacent sequences: A099966 A099967 A099968 * A099970 A099971 A099972

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane, Nov 13, 2004, based on correspondence from Artur Jasinski, Mar 25 2003

EXTENSIONS

More terms from Ryan Propper, Aug 18 2005

STATUS

approved