OFFSET
1,3
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
EXAMPLE
The first and second primes of the form 4*k+3 are 3 and 7, so a(1) = (7-3)/4 = 1.
MATHEMATICA
k=0; m=4; r=3; Do[s=Mod[Prime[n], m]; If[Equal[s, r], rp=ep; k=k+1; ep=Prime[n]; Print[(ep-rp)/4]; ], {n, 1, 1000}]
Differences[Select[Prime[Range[400]], IntegerQ[(#-3)/4]&]]/4 (* Harvey P. Dale, Apr 29 2022 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Labos Elemer, Apr 07 2003
STATUS
approved