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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 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS The even prime 2 is not split. LINKS 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 Cf. A000040, A002808. Sequence in context: A099470 A099254 A186731 * A300417 A121339 A307236 Adjacent sequences:  A180105 A180106 A180107 * A180109 A180110 A180111 KEYWORD base,nonn AUTHOR Parthasarathy Nambi, Aug 10 2010 EXTENSIONS More terms from Robert G. Wilson v, Aug 15 2010 STATUS approved

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Last modified February 27 15:59 EST 2020. Contains 332307 sequences. (Running on oeis4.)