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 A109989 4-almost primes (A014613) ordered alphabetically by where they occur in A000052. 1
 88, 84, 81, 54, 56, 40, 90 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS A109986 is primes ordered alphabetically by where they occur in A000052. A109987 is semiprimes ordered alphabetically by where they occur in A000052. A109988 is 3-almost primes ordered alphabetically by where they occur in A000052. LINKS EXAMPLE a(1) = 88 because eighty-eight is the first 4-almost prime in alphabetical order, there being no 1-digit 4-almost primes. a(2) = 84 because eighty-four is the second 2-digit 4-almost prime in alphabetical order. CROSSREFS Cf. A000052, A014613, A109986, A109987, A109988. Sequence in context: A033408 A298452 A299526 * A239154 A181469 A147317 Adjacent sequences:  A109986 A109987 A109988 * A109990 A109991 A109992 KEYWORD base,easy,nonn,word AUTHOR Jonathan Vos Post, Jul 07 2005 STATUS approved

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Last modified August 1 10:13 EDT 2021. Contains 346385 sequences. (Running on oeis4.)