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A071191 Least m>n such that the number of prime factors of m and n differ at most by 1. 3
2, 3, 4, 5, 6, 7, 9, 9, 10, 11, 13, 14, 14, 15, 17, 18, 19, 20, 21, 21, 22, 23, 25, 27, 26, 27, 28, 30, 31, 33, 33, 36, 34, 35, 37, 40, 38, 39, 41, 42, 43, 44, 46, 45, 46, 47, 49, 54, 50, 51, 52, 54, 55, 56, 57, 60, 58, 59, 61, 63, 62, 63, 65 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
abs(A001222(a(n)) - A001222(n)) <= 1.
LINKS
EXAMPLE
a(11) = 13 as 11 has one prime factor (counted with multiplicity) and 13 has 1 prime factor (counted with multiplicity), 13 the smallest number m > 11 such that the number of prime factors of m and 11 differ by at most 1. - David A. Corneth, Feb 23 2024
PROG
(PARI)
a(n) = {
my(b = bigomega(n));
for(i = n + 1, oo,
if(abs(bigomega(i)-b) <= 1,
return(i)
)
)
} \\ David A. Corneth, Feb 23 2024
CROSSREFS
Sequence in context: A323785 A327626 A179464 * A300903 A097428 A126072
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, May 15 2002
STATUS
approved

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Last modified June 12 12:13 EDT 2024. Contains 373331 sequences. (Running on oeis4.)