# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a075285 Showing 1-1 of 1 %I A075285 #8 Jun 24 2017 08:22:21 %S A075285 30,50,170,370,590,610,730,1370,1390,1910,1990,2290,3310,3730,4010, %T A075285 4990,5410,6070,6590,7190,7870,8770,9470,9970,10610,11090,11810,11930, %U A075285 12970,14470,15230,15310,16270,16570,16990,17330,18790,19130,20110 %N A075285 Interprimes which are of the form s*prime, s=10. %C A075285 Interprimes of the form s*prime are in A075277-A075296 ( s = 2 - 21 ). Case s=1 is impossible. %H A075285 Harvey P. Dale, Table of n, a(n) for n = 1..1000 %e A075285 370 is an interprime and 370/10 = 37 is prime. %t A075285 s=10; Select[Table[(Prime[n+1]+Prime[n])/2, {n, 2, 4000}], PrimeQ[ #/s]&] %t A075285 Select[Mean/@Partition[Prime[Range[2500]],2,1],PrimeQ[#/10]&] (* _Harvey P. Dale_, Jun 24 2017 *) %Y A075285 Cf. A075277-A075296. %K A075285 easy,nonn %O A075285 1,1 %A A075285 _Zak Seidov_, Sep 12 2002 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE