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Revision History for A363050 (Bold, blue-underlined text is an addition; faded, red-underlined text is a deletion.)

Showing all changes.
Lesser of two consecutive integers such that one has more prime factors (counted with multiplicity), but the other has more divisors.
(history; published version)
#9 by Michael De Vlieger at Sun May 14 23:47:27 EDT 2023
STATUS

proposed

approved

#8 by Jon E. Schoenfield at Sun May 14 21:55:15 EDT 2023
STATUS

editing

proposed

#7 by Jon E. Schoenfield at Sun May 14 21:53:45 EDT 2023
COMMENTS

The first pair of consecutive integers that are both terms is (728, 729), and the first run of three consecutive integers all appearing as terms begins at 127251 (see Examples). The first run of four consecutive integers appearing as terms begins at 4405832. Do arbitrarily long runs of consecutive integers occur?

#6 by Jon E. Schoenfield at Sun May 14 21:52:21 EDT 2023
COMMENTS

The first pair of consecutive integers that are both terms is (728, 729), and the first run of three consecutive integers all appearing as terms begins at 127251 (see Examples). The first run of four consecutive integers appearing as terms begins at 4405832. Do arbitrarily long runs of integers occur?

EXAMPLE

A run of four consecutive integers that are terms begins at 4405832.

#5 by Jon E. Schoenfield at Sun May 14 21:31:29 EDT 2023
EXAMPLE

A run of four consecutive integers that are terms begins at 4405832.

#4 by Jon E. Schoenfield at Sun May 14 21:25:51 EDT 2023
NAME

allocated for Jon E. Schoenfield

Lesser of two consecutive integers such that one has more prime factors (counted with multiplicity), but the other has more divisors.

DATA

495, 728, 729, 975, 1071, 1424, 1616, 1700, 1862, 1875, 2024, 2144, 2223, 2349, 2384, 2415, 2624, 2996, 3104, 3124, 3125, 3159, 3184, 3483, 3663, 4095, 4130, 4292, 4304, 4335, 4779, 4976, 5103, 5312, 5427, 5535, 5589, 5624, 5775, 6224, 6416, 6544, 6560, 6704

OFFSET

1,1

EXAMPLE

495 = 3*3*5*11 has 4 prime factors and 12 divisors, while 496 = 2*2*2*2*31 has 5 prime factors but only 10 divisors, so 495 is a term.

728 = 2*2*2*7*13, 729 = 3*3*3*3*3*3, and 730 = 2*5*73 have 5, 6, and 3 prime factors and 16, 7, and 8 divisors, respectively, so both 728 and 729 are terms.

127251 = 3*3*3*3*1571, 127252 = 2*2*29*1097, 127253 = 7*7*7*7*53, and 127254 = 2*3*127*167 have 5, 4, 5, and 4 prime factors, and 10, 12, 10, and 16 divisors, respectively, so 127251, 127252, and 127253 are all terms.

CROSSREFS
KEYWORD

allocated

nonn

AUTHOR

Jon E. Schoenfield, May 14 2023

STATUS

approved

editing

#3 by Jon E. Schoenfield at Sun May 14 21:25:51 EDT 2023
NAME

allocated for Jon E. Schoenfield

KEYWORD

recycled

allocated

#2 by Jack Braxton at Sun May 14 15:17:07 EDT 2023
NAME

allocated for Jack Braxton

KEYWORD

allocated

recycled

#1 by Jack Braxton at Sun May 14 13:07:53 EDT 2023
NAME

allocated for Jack Braxton

KEYWORD

allocated

STATUS

approved