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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

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A140600 Grand totals of prime factors in composite runs between two primes.

Original entry on oeis.org

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
Offset: 1

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Author

Enoch Haga, May 18 2008

Keywords

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).

Examples

			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.

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.
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Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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