This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A082552 #14 Oct 31 2013 12:17:22
%S A082552 1,1,2,5,6,12,21,31,58,111,184,356,665,1223,2260,4227,7930,15095,
%T A082552 28334,53822,102317,195012,373001,714405,1370698,2633383,5067643,
%U A082552 9765457,18846711,36413982,70431270,136391723,264384100,512959093,996173830
%N A082552 Number of sets of distinct primes, the greatest of which is prime(n), whose arithmetic mean is an integer.
%C A082552 The sum of the first 23 primes gives 874 = 23*38, see A045345. - _Alois P. Heinz_, Aug 02 2009
%H A082552 Alois P. Heinz, <a href="/A082552/b082552.txt">Table of n, a(n) for n = 1..100</a>
%e A082552 a(4) = 5: prime(4) = 7 and the five sets are (5+7)/2 = 6, 7/1 = 7, (3+7)/2 = 5, (2+3+7)/3 = 4, (3+5+7)/3 = 5.
%p A082552 b:= proc(t,i,m,h) option remember; if h=0 then `if` (t=0, 1, 0) elif i<1 or h>i then 0 else b (t, i-1, m, h) +b((t+ithprime(i)) mod m, i-1, m, h-1) fi end: a:= n-> add(b(ithprime(n) mod m, n-1, m, m-1), m=1..n): seq (a(n), n=1..40); # _Alois P. Heinz_, Aug 02 2009
%t A082552 f[n_] := Block[{c = 0, k = n, lst = Prime@ Range@n, np = Prime@n, slst}, While[k < 2^n, slst = Subsets[lst, All, {k}]; If[Last@slst == np && Mod[Plus @@ slst, Length@slst] == 0, c++ ]; k++ ]; c]; Do[ Print[{n, f@n} // Timing], {n, 24}] (* _Robert G. Wilson v_ *)
%Y A082552 Cf. A051293, A072701.
%K A082552 nonn
%O A082552 1,3
%A A082552 _Naohiro Nomoto_, May 03 2003
%E A082552 a(22)-a(24) from _Robert G. Wilson v_, Jan 19 2007
%E A082552 Corrected a(23) and extended by _Alois P. Heinz_, Aug 02 2009