OFFSET
1,1
LINKS
Zak Seidov, Table of n, a(n) for n = 1..1000
FORMULA
a(n) = A077388(n)/n.
EXAMPLE
a(5) = 79 because the average of the 5 consecutive primes 71, 73, 79, 83, and 89 is 79, and this is the smallest such set: for example, the average of 7, 11, 13, 17, and 19 is 13.4, which is not an integer.
MATHEMATICA
f[n_] := Block[{k = 1, t}, While[t = Table[Prime[i], {i, k, k + n - 1}]; Mod[Plus @@ t, n] > 0, k++ ]; t]; Mean /@ Table[f[n], {n, 58}] (* Ray Chandler, Oct 09 2006 *)
PROG
(PARI) a(n) = {my(v=primes(n), s=vecsum(v), p=prime(n)); while(s%n, s-=v[1]-p=nextprime(p+1); v=concat(v[2..n], p)); s/n; } \\ Jinyuan Wang, Sep 05 2020
CROSSREFS
KEYWORD
nonn
AUTHOR
Amarnath Murthy, Nov 06 2002
EXTENSIONS
More terms from Sascha Kurz, Jan 30 2003
Change to definition based on comment by Zak Seidov, Mar 20 2013
STATUS
approved