# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a031938 Showing 1-1 of 1 %I A031938 #19 Apr 30 2024 05:43:30 %S A031938 887,1637,3089,3413,3947,5717,5903,5987,6803,7649,8243,8543,8783,8867, %T A031938 9257,10223,10433,10667,11027,11093,11177,11447,11597,11657,11867, %U A031938 11987,13127,13421,13649,14087,14177,15473,16943,17519,17807 %N A031938 Lower prime of a difference of 20 between consecutive primes. %H A031938 Remi Eismann, Table of n, a(n) for n = 1..10000 %H A031938 Index entries for primes, gaps between %F A031938 a(n) = prime(A320708(n)). - _R. J. Mathar_, Apr 30 2024 %e A031938 887 is a term as the next prime is 907. %t A031938 (*M6*) a=887; S={}; Do[b=NextPrime[a]; If[b-a==20,AppendTo[S,a]]; a=b,{10^4}]; S [_Zak Seidov_, Aug 14 2009] %t A031938 Transpose[Select[Partition[Prime[Range[2000]], 2, 1], Last[#] - First[#] == 20 &]][[1]] (* _Bruno Berselli_, Apr 09 2013 *) %o A031938 (Magma) [p: p in PrimesUpTo(20000) | NextPrime(p)-p eq 20]; // _Bruno Berselli_, Apr 09 2013 %K A031938 nonn %O A031938 1,1 %A A031938 _Jeff Burch_ %E A031938 Entries and b-file checked by _Zak Seidov_, Aug 14 2009 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE