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A081102 Numbers k such that the first k digits of log_10(2) after the decimal point are primes. 0
1, 64, 1126, 1653, 13680, 27453 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..6.

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} ]

CROSSREFS

Cf. A007524.

Sequence in context: A191494 A269000 A189276 * A250171 A128987 A240788

Adjacent sequences:  A081099 A081100 A081101 * A081103 A081104 A081105

KEYWORD

nonn,base,more

AUTHOR

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

EXTENSIONS

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

STATUS

approved

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Last modified May 18 03:03 EDT 2021. Contains 343994 sequences. (Running on oeis4.)