# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a056928 Showing 1-1 of 1 %I A056928 #17 Oct 14 2023 23:43:58 %S A056928 4,9,15,26,34,50,64,81,99,120,144,170,195,225,254,288,324,363,399,441, %T A056928 483,532,574,625,675,730,780,846,897,960,1026,1089,1158,1226,1294, %U A056928 1370,1443,1517,1599,1681,1768,1854,1941,2022,2121,2210,2303,2405,2490 %N A056928 Average of the smallest prime greater than n^2 and the largest prime less than n^2. %H A056928 Hugo Pfoertner, Table of n, a(n) for n = 2..10000 %F A056928 a(n) = (A007491(n) - A053001(n))/2. %F A056928 a(n) = A000290(n) + (A053000(n) - A056927(n))/2. %F A056928 a(n) = A000290(n) - A056929(n). %e A056928 a(4)=15 because the smallest prime greater than 4^2 is 17, the largest prime less than 4^2 is 13, and the average of 17 and 13 is 15. %t A056928 Table[n2=n^2;(NextPrime[n2,-1]+NextPrime[n2])/2,{n,2,100}] (* _Vladimir Joseph Stephan Orlovsky_, Mar 09 2011 *) %o A056928 (PARI) a(n) = (nextprime(n^2) + precprime(n^2))/2; \\ _Michel Marcus_, May 20 2018 %Y A056928 Cf. A007491, A053000, A053001, A056927, A056929, A056930, A056931. %K A056928 easy,nonn %O A056928 2,1 %A A056928 _Henry Bottomley_, Jul 12 2000 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE