OFFSET
1,1
COMMENTS
a(k) has the largest equal 'gap' between the nearest primes so far, i.e.; (the sum of the two nearest primes)/2 equals a(k).
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..72
MATHEMATICA
f[n_] := Block[{k}, If[ OddQ[n], k = 2, k = 1]; While[ !PrimeQ[n - k] || !PrimeQ[n + k], k += 2]; k]; t = Table[f[n], {n, 4, 10^4}]; u = Table[0, {80}]; Do[a = t[[n]]; If[a < 81 && u[[a]] == 0, u[[a]] = n + 3], {n, 10^4}]; a = 0; lst = {}; Do[ If[u[[n]] > a, a = u[[n]]; AppendTo[lst, a]], {n, 80}]; lst
CROSSREFS
KEYWORD
nonn
AUTHOR
Benoit Cloitre and Robert G. Wilson v, Mar 28 2005
STATUS
approved