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A180108
Integers where the primes are split into two consecutive numbers.
1
0, 1, 2, 1, 2, 4, 2, 3, 6, 3, 4, 8, 9, 10, 5, 6, 12, 6, 7, 14, 15, 16, 8, 9, 18, 9, 10, 20, 21, 22, 11, 12, 24, 25, 26, 27, 28, 14, 15, 30, 15, 16, 32, 33, 34, 35, 36, 18, 19, 38, 39, 40, 20, 21, 42, 21, 22, 44, 45, 46, 23, 24, 48, 49, 50, 51, 52, 26, 27, 54, 55, 56, 57, 58, 29, 30
OFFSET
0,3
COMMENTS
The even prime 2 is not split.
EXAMPLE
The prime 29 is split into 14 and 15.
MATHEMATICA
f[n_] := If[ !PrimeQ@ n || n == 2, n, {(n - 1)/2, (n + 1)/2}]; Array[ f, 60, 0] // Flatten (* Robert G. Wilson v, Aug 15 2010 *)
CROSSREFS
Sequence in context: A099470 A099254 A186731 * A300417 A121339 A307236
KEYWORD
base,nonn
AUTHOR
Parthasarathy Nambi, Aug 10 2010
EXTENSIONS
More terms from Robert G. Wilson v, Aug 15 2010
STATUS
approved