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A071192
Least m>n such that the number of prime factors of m and n differ by 1.
3
2, 4, 4, 5, 6, 7, 9, 9, 11, 11, 14, 14, 14, 17, 17, 18, 21, 21, 21, 21, 23, 23, 25, 27, 27, 27, 33, 33, 33, 33, 33, 36, 37, 37, 37, 42, 38, 41, 41, 42, 46, 46, 46, 46, 46, 47, 49, 54, 50, 51, 52, 54, 55, 63, 59, 63, 59, 59, 62, 63, 62, 63, 65
OFFSET
1,1
LINKS
FORMULA
abs(A001222(a(n)) - A001222(n)) = 1.
EXAMPLE
a(11) = 14 as 11 has one prime factor (counted with multiplicity) and 14 has 2 prime factors (counted with multiplicity) 14 the smallest number m > 11 such that the number of prime factors of m and 11 differ by 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: A196259 A214880 A071193 * A295012 A308629 A100921
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, May 15 2002
STATUS
approved