A178462 Numbers k such that prime(k) mod k > k/2.

3, 4, 9, 10, 11, 19, 20, 22, 23, 24, 25, 26, 27, 28, 29, 30, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 70, 71, 72, 116, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142

Offset

1,1

Comments

The sequence consists largely of long runs of consecutive integers. However, there are also a few isolated integers such that the distance to both neighbor terms is greater than 1: 116, 4136, 4138, 4141, 4143, 4151, 6458, 63423, 100363.

Links

Table of n, a(n) for n=1..62.

Example

3 is a term because prime(3) mod 3 = 5 mod 3 = 2 > 3/2;
4 is a term because prime(4) mod 4 = 7 mod 4 = 3 > 4/2;
9 is a term because prime(9) mod 9 = 23 mod 9 = 5 > 9/2.

Mathematica

Select[Range[150], Mod[Prime[#], #]>#/2&]  (* Harvey P. Dale, Jan 18 2011 *)

Prog

(PARI) for(n=1, 200, prime(n)%n>n/2&print1(n, ", "))
(Magma) [ n: n in [1..150] | NthPrime(n) mod n gt n/2 ];

Crossrefs

Cf. companion sequence A178502.

Sequence in context: A134025 A109406 A280632 * A010376 A010388 A283973

Adjacent sequences: A178459 A178460 A178461 * A178463 A178464 A178465

Keyword

nonn

Author

Zak Seidov, Dec 24 2010

Status

approved