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A277730
Irregular triangle read by rows: T(n,k) = number of times a gap of 2k occurs between the first n successive odd primes.
2
1, 2, 2, 1, 3, 1, 3, 2, 4, 2, 4, 3, 4, 3, 1, 5, 3, 1, 5, 3, 2, 5, 4, 2, 6, 4, 2, 6, 5, 2, 6, 5, 3, 6, 5, 4, 7, 5, 4, 7, 5, 5, 7, 6, 5, 8, 6, 5, 8, 6, 6, 8, 7, 6, 8, 7, 7, 8, 7, 7, 1, 8, 8, 7, 1, 9, 8, 7, 1, 9, 9, 7, 1, 10, 9, 7, 1, 10, 10, 7, 1, 10, 10, 7, 1, 0, 0, 1, 10, 11, 7, 1, 0, 0, 1
OFFSET
2,2
LINKS
Lars Blomberg, Table of n, a(n) for n = 2..9997 (the first 703 rows)
EXAMPLE
Triangle begins:
1,
2,
2, 1,
3, 1, <- gaps in 3,5,7,11,13 are 2 (3 times), 4 (once)
3, 2,
4, 2,
4, 3,
4, 3, 1,
5, 3, 1,
5, 3, 2,
5, 4, 2,
6, 4, 2,
6, 5, 2,
6, 5, 3,
6, 5, 4,
7, 5, 4,
7, 5, 5,
7, 6, 5,
8, 6, 5,
...
CROSSREFS
Sequence in context: A259176 A237591 A359979 * A174167 A374064 A159876
KEYWORD
nonn,look,tabf
AUTHOR
N. J. A. Sloane, Nov 06 2016
STATUS
approved