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A140599 Grand total of prime factors in composite runs between two primes: first composite. 1
4, 6, 12, 14, 18, 24, 54, 62, 68, 72, 80, 90, 108, 110, 158, 192, 234, 258, 264, 318, 338, 350, 354, 380, 420, 432, 458, 462, 570, 588, 602, 632, 662, 858, 978, 992, 1050, 1088, 1094, 1152, 1172, 1290, 1302, 1304, 1400, 1428, 1434, 1482, 1532, 1722, 1824, 1862 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..52.

FORMULA

Compute composite runs between two primes. If the grand total of prime factors in each run is also prime, add the firat composite to the sequence.

{A008864(j): sum_{k=A008864(j)..A006093(j+1)} A105221(k) in A000040}. - R. J. Mathar, May 19 2008

EXAMPLE

In the composite run between primes 23 and 29 there are five composites. The sum of prime factors in all 5 composites is 37 (3+2+5+13+2+3+7+2). The first composite in this run is 24, a(6) and the last is 28.

CROSSREFS

Cf. A140600.

Sequence in context: A163097 A110178 A318712 * A282280 A320495 A047406

Adjacent sequences:  A140596 A140597 A140598 * A140600 A140601 A140602

KEYWORD

easy,nonn

AUTHOR

Enoch Haga, May 18 2008

STATUS

approved

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Last modified October 22 16:24 EDT 2019. Contains 328318 sequences. (Running on oeis4.)