A108719 Primes which can be partitioned into a sum of distinct primes in more than one way.

5, 7, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97, 101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199, 211, 223, 227, 229, 233, 239, 241, 251, 257, 263, 269, 271, 277, 281

Offset

1,1

Comments

Presumably this consists of all primes except 2, 3 and 11 - see A000586.

Prime p is in the sequence iff A000586(p)>1.

Links

Table of n, a(n) for n=1..57.

Formula

a(n) = prime(n+3) for n > 2. [Charles R Greathouse IV, Feb 09 2012]

Example

5 is a member because 5 can be written in two ways: 5 = 2+3; 19 because 19 = 3+5+11.

Prog

(PARI) a(n)=if(n>2, prime(n+3), 3+2*n) \\ Charles R Greathouse IV, Feb 09 2012
(Python)
from sympy import prime
a = lambda n: prime(n+3) if n>2 else 3+(n<<1) # Darío Clavijo, Oct 23 2023

Crossrefs

Cf. A000586.

Sequence in context: A236204 A152810 A260405 * A162707 A216769 A216743

Adjacent sequences: A108716 A108717 A108718 * A108720 A108721 A108722

Keyword

easy,nonn,changed

Author

Giovanni Teofilatto, Jun 21 2005; corrected Jun 23 2005

Extensions

Edited and extended by Ray Chandler, Jul 03 2005

Status

approved