A076240 Remainder when 2nd order prime pp(n) = A006450(n) is divided by n-th prime = A000040(n).

1, 2, 1, 3, 9, 2, 8, 10, 14, 22, 3, 9, 15, 19, 23, 29, 41, 39, 63, 69, 2, 6, 16, 16, 24, 42, 48, 52, 54, 52, 74, 84, 88, 102, 114, 122, 134, 152, 156, 166, 168, 1, 7, 13, 19, 23, 31, 71, 71, 73, 73, 65, 77, 91, 79, 91, 109, 115, 125, 137, 149, 155, 185, 197, 203, 197, 235

Offset: 1

Author

Labos Elemer, Oct 08 2002

Keywords

• nonn
• look

Examples

			a(4) = 3 since prime(prime(4)) (mod prime(4)) = prime(7) (mod 7) = 17 (mod 7) = 3. - _Michael De Vlieger_, Mar 25 2017
		

Links

• Alois P. Heinz, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A006450, A038580, A049090, A049203, A049202, A057809, A076241, A076242, A076243.

Programs

Maple

a:= n-> (p-> irem(ithprime(p), p))(ithprime(n)):
seq(a(n), n=1..70);  # Alois P. Heinz, Oct 09 2015

Mathematica

Table[Mod @@ Map[Nest[Prime, n, #] &, {2, 1}], {n, 65}] (* Michael De Vlieger, Mar 25 2017 *)

PARI

a(n) = prime(prime(n)) % prime(n); \\ Michel Marcus, Mar 25 2017

Formula

a(n) = prime^2(n) mod prime(n) = A006450(n) mod A000040(n).