|
%I #17 Oct 14 2023 23:43:58
%S 4,9,15,26,34,50,64,81,99,120,144,170,195,225,254,288,324,363,399,441,
%T 483,532,574,625,675,730,780,846,897,960,1026,1089,1158,1226,1294,
%U 1370,1443,1517,1599,1681,1768,1854,1941,2022,2121,2210,2303,2405,2490
%N Average of the smallest prime greater than n^2 and the largest prime less than n^2.
%H Hugo Pfoertner, <a href="/A056928/b056928.txt">Table of n, a(n) for n = 2..10000</a>
%F a(n) = (A007491(n) - A053001(n))/2.
%F a(n) = A000290(n) + (A053000(n) - A056927(n))/2.
%F a(n) = A000290(n) - A056929(n).
%e 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 Table[n2=n^2;(NextPrime[n2,-1]+NextPrime[n2])/2,{n,2,100}] (* _Vladimir Joseph Stephan Orlovsky_, Mar 09 2011 *)
%o (PARI) a(n) = (nextprime(n^2) + precprime(n^2))/2; \\ _Michel Marcus_, May 20 2018
%Y Cf. A007491, A053000, A053001, A056927, A056929, A056930, A056931.
%K easy,nonn
%O 2,1
%A _Henry Bottomley_, Jul 12 2000
|
