1,1

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

with(numtheory): pre:=0: for n from 1 to 3000 do if isprime(n) and isprime(n+4) then if pre<>0 then printf("%d, ", n-pre) fi: pre:=n fi od: # C. Ronaldo

Differences[Select[Prime[Range[500]], PrimeQ[# + 4]&]] (* Vincenzo Librandi, Jul 11 2013 *)

First differences of A023200.

Cf. A227346.

Sequence in context: A079033 A272771 A077038 * A019090 A145692 A295512

Adjacent sequences: A053317 A053318 A053319 * A053321 A053322 A053323

nonn,easy

Labos Elemer, Mar 06 2000

approved