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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
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
KEYWORD
easy,nonn
AUTHOR
Enoch Haga, May 18 2008
STATUS
approved

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Last modified April 24 13:13 EDT 2024. Contains 371947 sequences. (Running on oeis4.)