OFFSET
1,1
LINKS
Harvey P. Dale, Table of n, a(n) for n = 1..1000
EXAMPLE
a(3)=11=4*3-1, a(4)=13=4*3+1
MAPLE
i:=1:for k from 1 to 600 do if isprime(4*k-1) and isprime(4*k+1) then a[i]:=4*k-1:a[i+1]:=4*k+1: i:=i+2 fi od: seq(a[n], n=1..i-1);
MATHEMATICA
Select[Partition[Prime[Range[300]], 2, 1], #[[2]]-#[[1]]==2&&Divisible[ Mean[ #], 4]&]//Flatten (* Harvey P. Dale, May 17 2021 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Miklos Kristof, Sep 21 2006
STATUS
approved