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A054656 Number of primes <=n which do not appear in any partitions of n into distinct primes. 0
0, 0, 0, 1, 2, 0, 3, 1, 2, 2, 0, 4, 1, 3, 1, 1, 1, 1, 1, 2, 1, 1, 1, 2, 1, 1, 0, 1, 0, 1, 1, 0, 1, 1, 0, 2, 0, 1, 1, 0, 0, 1, 0, 1, 1, 1, 0, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,5

COMMENTS

Conjecture: if n >= 23 then a(n)=2 if both (n-6) and (n-4) are prime, a(n)=1 if one of (n-6), (n-4) or (n-1) is prime, a(n)=0 otherwise

LINKS

Table of n, a(n) for n=0..47.

EXAMPLE

a(22)=1 since 22=2+7+13=2+3+17=5+17=3+19, so the primes 2,3,5,7,13,17 and 19 appear at least once but 11 does not.

CROSSREFS

Cf. A000586.

Sequence in context: A293813 A218585 A279507 * A080096 A322978 A294142

Adjacent sequences:  A054653 A054654 A054655 * A054657 A054658 A054659

KEYWORD

nonn

AUTHOR

Henry Bottomley, Apr 17 2000

STATUS

approved

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Last modified November 17 23:26 EST 2019. Contains 329242 sequences. (Running on oeis4.)