The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A081102 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
Showing all changes.

A081102

Numbers k such that the first k digits of log_10(2) after the decimal point are primes.
(history; published version)

#6 by Bruno Berselli at Wed Jan 27 05:34:58 EST 2021

STATUS

reviewed

approved

#5 by Michel Marcus at Wed Jan 27 01:51:28 EST 2021

STATUS

proposed

reviewed

#4 by Amiram Eldar at Wed Jan 27 01:44:03 EST 2021

STATUS

editing

proposed

#3 by Amiram Eldar at Wed Jan 27 01:24:59 EST 2021

NAME

First n Numbers k such that the first k digits of Log_log_10 (2 ) after the decimal point are primes.

DATA

1, 64, 1126, 1653, 13680, 27453

OFFSET

0,1,2

CROSSREFS

Cf. A007524.

EXTENSIONS

Offset corrected and a(5)-a(6) added by Amiram Eldar, Jan 27 2021

STATUS

approved

editing

#2 by N. J. A. Sloane at Wed Dec 06 03:00:00 EST 2006

NAME

First n digits of Log_10 2 after the decimal point are primeprimes.

KEYWORD

nonn,base,more,new

#1 by N. J. A. Sloane at Fri May 16 03:00:00 EDT 2003

NAME

First n digits of Log_10 2 after the decimal point are prime.

DATA

1, 64, 1126, 1653

OFFSET

0,2

EXAMPLE

1 is listed because 3 is prime but 5 is not listed because 30102 is not prime.

MATHEMATICA

Do[ If[ PrimeQ[ FromDigits[ RealDigits[ N[ Log[10, 2], n + 10], 10, n] [ [1] ] ] ], Print[n] ], {n, 1, 10000} ]

KEYWORD

nonn,base,more

AUTHOR

John Sillcox (JMS21187(AT)aol.com), Apr 15 2003

STATUS

approved