A066752 - OEIS

%I #14 Jan 04 2016 01:36:18

%S 1,1,2,1,6,7,2,1,2,1,4,1,14,1,16,1,6,1,4,3,2,1,12,5,2,3,4,1,10,1,32,

%T 33,2,35,6,1,2,1,8,1,6,1,4,1,2,1,4,7,2,1,26,1,2,1,2,3,2,1,2,1,2,21,4,

%U 13,2,1,4,1,2,1,6,1,2,1,76,1,78,1,2,1,2,1,12,1,2,3,2,1,6,1,4,3,2,1,4,1,2,9,4

%N a(n) = gcd(prime(n)+1, n+1).

%H Harry J. Smith, <a href="/A066752/b066752.txt">Table of n, a(n) for n = 1..1000</a>

%e a(23) = gcd(prime(23)+1,23+1) = gcd(83+1,24) = gcd(84,24) = 12*gcd(7,2) = 12.

%t Table[GCD[Prime[w]+1, w+1], {w, 1, 128}]

%o (PARI) { for (n=1, 1000, write("b066752.txt", n, " ", gcd(prime(n) + 1, n + 1)) ) } \\ _Harry J. Smith_, Mar 22 2010

%Y Cf. A000040.

%Y Cf. A084309-A084316.

%K nonn

%O 1,3

%A _Reinhard Zumkeller_, Jan 16 2002

%E More terms from _Labos Elemer_, Jun 13 2003