In the first set you'll notice no doubt six consecutive primes 5, 7, 11, 13, 17 and 19.A050780 - (n + sopf_n = m) and (m - sopf_m = n). Sequence gives values of n.
All the members of the first two sets are semi-primes i.e. having exactly two distinct factors.
The third set has a common prime divisor > 2 to all members namely 179.
Curious is also the loop taken counterclockwise of the middle digits
of the factors of the second set starting from 443.
It starts with a 4, then a 5, then a ... up to and then finally a 9 in factor 397.
373 * 467
383 * 457
397 * 443
Common prime divisor of the members of the composite triplet
(298687992, 298688708, 298689424) which are in a bi-directional
'sum of prime factors' (i.e., 716) progression/retrogression.
Some OEIS entries
A050781 - (n + sopf_n = m) and (m - sopf_m = n). Sequence gives values of m.
A057874 - Sets of three composites in bidirectional 'sum of prime factors' progression/retrogression.
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