23374

Appears in sequences

• Coordination sequence for Cr3Si, Cr position.at n=39A009928
• Number of asymmetric loops (quasigroups with an identity element).at n=7A057998
• Numbers k such that usigma(k) = phi(k)*omega(k), where omega(k) is the number of distinct prime divisors of k.at n=15A063795
• Numbers n such that the arithmetic, geometric and harmonic means of phi(n) and sigma(n) are all integers.at n=16A065146
• Numbers k such that sigma(k) = bigomega(k) * phi(k).at n=10A067238
• Numbers k such that sigma(k) = 4*phi(k).at n=12A068390
• Numbers k such that sigma(k) = phi(k*bigomega(k)).at n=10A068400
• Numbers k such that sigma(k) = phi(k)*omega(k).at n=6A073567
• Position of first repeat of the opening sequence of length n occurring after the first repeat of the opening sequence of length n-1 in the Kolakoski sequence (A000002).at n=36A074300
• Squarefree balanced numbers (i.e., squarefree members of A020492).at n=36A078557
• Numbers such that Sigma(m)*UnitarySigma(m)= k*UnitaryPhi(m)^2, for some integer k.at n=42A122839
• Numbers m such that UnitarySigma(m)^2 = k*Sigma(m)*UnitaryPhi(m), for some integer k.at n=42A123041
• a(n) is the smallest number whose English name has the letter "f" in the n-th position, or -1 if no such number exists.at n=38A164794
• a(n) is the smallest number whose English name has the letter "u" in the n-th position, or -1 if no such number exists.at n=40A164797
• Number of -n..n arrays x(0..3) of 4 elements with zero sum and nonzero second differences.at n=15A200554
• Number of (w,x,y,z) with all terms in {1,...,n} and 2*w*x<3*y*z.at n=14A211920
• Number of Dyck n-paths all of whose ascents have lengths equal to 1 (mod 4).at n=15A212384
• Numbers k such that gcd(sigma(k), phi(k)) (A009223) attains record values.at n=25A222711
• Rank of first single 1 in A000002 such that A249949 takes the value n.at n=6A249952
• Numbers x such that (-1)sigma(x) | sigma(x), where (-1)sigma(x) is defined in A049060 and sigma(x) is the sum of the divisors of x (A000203).at n=43A258077