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A145061
Number of pairs of odd numbers that separate two consecutive twin prime pairs
1
0, 2, 2, 5, 5, 8, 5, 14, 2, 14, 5, 14, 5, 2, 14, 5, 14, 5, 14, 17, 35, 5, 14, 29, 23, 14, 8, 11, 8, 74, 5, 2, 14, 11, 68, 5, 8, 5, 14, 29, 38, 23, 5, 5, 8, 53, 11, 14, 2, 59, 5, 23, 14, 11, 32, 41, 2, 26, 8, 23, 14, 26, 2, 11, 8, 5, 47, 14, 20, 14, 20
OFFSET
1,2
COMMENTS
Example: a(3) = 2 because the third twin prime pair is (11, 13) and there are two pairs of odd numbers between (11, 13) and its immediate predecessor, (5,7), namely (7, 9) and (9, 11).
FORMULA
a(n) = (A001359(n+1) - (A001359(n) + 2))/2 = (A001359(n+1) - A006512(n))/2. - Michel Marcus, Sep 04 2013
PROG
(PARI) lista(nn) = {prm = primes(nn); gtp = select(p->isprime(p-2), prm); ltp = select(p->isprime(p+2), prm); for (i=1, #ltp-1, print1((ltp[i+1] - gtp[i])/2, ", "); ); } \\ Michel Marcus, Sep 04 2013
CROSSREFS
Sequence in context: A307984 A370585 A167177 * A168236 A035624 A340223
KEYWORD
nonn
AUTHOR
John Austin Curry (acurry(AT)mckoolsmith.com), Sep 30 2008
EXTENSIONS
More terms from Michel Marcus, Sep 04 2013
STATUS
approved