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A108719
Primes which can be partitioned into a sum of distinct primes in more than one way.
0
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.
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
KEYWORD
easy,nonn
AUTHOR
Giovanni Teofilatto, Jun 21 2005; corrected Jun 23 2005
EXTENSIONS
Edited and extended by Ray Chandler, Jul 03 2005
STATUS
approved