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Residues mod 4 of the n-th difference between consecutive primes.
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%I #19 Jul 07 2022 16:19:42

%S 1,2,2,0,2,0,2,0,2,2,2,0,2,0,2,2,2,2,0,2,2,0,2,0,0,2,0,2,0,2,0,2,2,2,

%T 2,2,2,0,2,2,2,2,2,0,2,0,0,0,2,0,2,2,2,2,2,2,2,2,0,2,2,2,0,2,0,2,2,2,

%U 2,0,2,0,2,2,0,2,0,0,0,2,2,2,2,2,0,2,0,0,2,0,0,0,0,0,0,2,0,2,2,2,2,2,2,2,2

%N Residues mod 4 of the n-th difference between consecutive primes.

%H Michael De Vlieger, <a href="/A080378/b080378.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n) = A001223(n) mod 4.

%t Table[Mod[Prime[w+1]-Prime[w], 4], {w, 1, 256}]

%t Mod[Differences[Prime[Range[200]]], 4] (* _Zak Seidov_, Jun 26 2015 *)

%o (Python)

%o from sympy import prime

%o def A080378(n): return (prime(n+1)-prime(n))&3 # _Chai Wah Wu_, Jul 07 2022

%Y Sequences related to the differences between successive primes: A001223 (Delta(p)), A028334, A080378, A104120, A330556-A330561.

%K nonn

%O 1,2

%A _Labos Elemer_, Mar 04 2003