The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A272143 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
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A272143

For a given n, and any m less than n-1, the total number of primes of the form 2^n-2^m-1.
(history; published version)

#16 by Michael De Vlieger at Thu Nov 09 08:55:00 EST 2023

STATUS

reviewed

approved

#15 by Michel Marcus at Thu Nov 09 00:57:34 EST 2023

STATUS

proposed

reviewed

#14 by Michael S. Branicky at Thu Nov 09 00:30:45 EST 2023

STATUS

editing

proposed

#13 by Michael S. Branicky at Thu Nov 09 00:30:43 EST 2023

PROG

(Python)

from sympy import isprime

def a(n): return sum(1 for i in range(n-1) if isprime(2**n-1-2**i))

print([a(n) for n in range(1, 81)]) # Michael S. Branicky, Nov 09 2023

STATUS

approved

editing

#12 by Bruno Berselli at Sun Apr 24 16:49:28 EDT 2016

STATUS

reviewed

approved

#11 by R. J. Mathar at Sun Apr 24 16:44:50 EDT 2016

STATUS

proposed

reviewed

#10 by R. J. Mathar at Sun Apr 24 16:06:50 EDT 2016

STATUS

editing

proposed

#9 by R. J. Mathar at Sun Apr 24 16:06:46 EDT 2016

COMMENTS

Essentially the same as A095058. - R. J. Mathar, Apr 24 2016

STATUS

approved

editing

#8 by N. J. A. Sloane at Fri Apr 22 22:44:28 EDT 2016

STATUS

editing

approved

#7 by N. J. A. Sloane at Fri Apr 22 22:44:23 EDT 2016

NAME

For a given n, and any m less than n-1, the total number of primes of the form 2^n-2^m-1.

STATUS

proposed

editing