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A140600 Grand totals of prime factors in composite runs between two primes. 1
2, 5, 5, 19, 5, 37, 83, 79, 59, 5, 53, 167, 5, 67, 179, 5, 239, 277, 263, 701, 479, 43, 439, 349, 17, 5, 281, 23, 29, 367, 397, 947, 1129, 29, 887, 739, 17, 149, 769, 5, 1361, 53, 43, 857, 1723, 29, 1861, 37, 2111, 53, 857, 983, 1699, 23, 907, 599, 1283, 29, 281, 23, 499 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
In this sequence a run consists of three or more terms, the first prime, one or more composites and the last prime. The values of the two primes are not included in the grand total of prime factors (only the prime factors in the composites).
LINKS
FORMULA
Compute composite runs between two primes. If the grand total of prime factors in each run is also prime, add the prime grand total to the sequence.
EXAMPLE
In a(6) the grand total is 37 because that is the prime sum of all the prime factors of composites in the composite run beginning at 24 (between primes 23 and 29).
CROSSREFS
Cf. A140599.
Sequence in context: A165659 A154816 A367299 * A056396 A085043 A338586
KEYWORD
easy,nonn
AUTHOR
Enoch Haga, May 18 2008
STATUS
approved

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Last modified March 28 20:05 EDT 2024. Contains 371254 sequences. (Running on oeis4.)