The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A216292

(Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
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A216292

Values of k such that there is exactly one prime between 10k and 10k + 9.
(history; published version)

#32 by Michael De Vlieger at Fri Sep 23 10:14:56 EDT 2022

STATUS

reviewed

approved

#31 by Joerg Arndt at Fri Sep 23 10:14:31 EDT 2022

STATUS

proposed

reviewed

#30 by Chai Wah Wu at Fri Sep 23 09:48:25 EDT 2022

STATUS

editing

proposed

#29 by Chai Wah Wu at Fri Sep 23 09:48:21 EDT 2022

PROG

(Python)

from itertools import count, islice

from sympy import isprime

def A216292_gen(startvalue=1): # generator of terms >= startvalue

return filter(lambda k: sum(int(isprime(10*k+i)) for i in (1, 3, 7, 9)) == 1, count(max(1, startvalue)))

A216292_list = list(islice(A216292_gen(), 30)) # Chai Wah Wu, Sep 23 2022

STATUS

approved

editing

#28 by Hugo Pfoertner at Tue Jun 21 04:22:51 EDT 2022

STATUS

reviewed

approved

#27 by Michel Marcus at Tue Jun 21 02:37:56 EDT 2022

STATUS

proposed

reviewed

#26 by Jon E. Schoenfield at Tue Jun 21 00:17:22 EDT 2022

STATUS

editing

proposed

#25 by Jon E. Schoenfield at Tue Jun 21 00:17:21 EDT 2022

NAME

Values of n k such that there is exactly one prime between 10n 10k and 10n 10k + 9.

PROG

(MAGMAMagma) [n: n in [1..200] | IsOne(#PrimesInInterval(10*n, 10*n+9))]; // Bruno Berselli, Sep 04 2012

STATUS

approved

editing

#24 by Harvey P. Dale at Wed Feb 04 18:11:51 EST 2015

STATUS

editing

approved

#23 by Harvey P. Dale at Wed Feb 04 18:11:45 EST 2015

MATHEMATICA

Select[Range[200], PrimePi[10#+9]-PrimePi[10#]==1&] (* Harvey P. Dale, Feb 04 2015 *)

STATUS

approved

editing