167580

Appears in sequences

• a(n) is least k such that k and 9k are anagrams in base n (written in base 10).at n=1A023101
• a(n) = n^2*(n-1)*(n-2).at n=19A047929
• Numbers m such that sigma(m)/m is equal to sigma(k)/k for some k being superabundant (A004394).at n=43A073349
• Least common multiple of cycle sizes in range [A014137(n-1)..A014138(n-1)] of permutations A085169/A085170.at n=7A086587
• Numbers k such that k*sigma(k)*sigma(sigma(k)) is a square.at n=10A116004
• Numbers with prime factorization pqr^2s^2t^2.at n=11A190379
• Numbers k for which sigma(k)/k - 5/7 is an integer.at n=4A218412
• Numbers k such that k = Sum_{i=1..j} (d_i mod d), where d_i are their aliquot parts and d is one of them.at n=21A265646
• G.f.: x^2 * f''(x), where f(x) = Product_{k>=1} 1 / (1 - x^k).at n=19A278406
• Numbers n such that the set of prime divisors of n is equal to the set of prime divisors of sum of proper divisors of n while n is not in A027598.at n=21A286876
• Indices of the Sylvester primes (A375543) in the primes (A000040).at n=25A375545
• Numbers x such that there exist three integers 0<x<=y<=z and t>0 such that sigma(x)^2 = sigma(y)^2 = sigma(z)^2 = x^2 + y^2 + z^2 + t^2.at n=43A385531
• Integers x such that sigma(x)^2 - 3*x^2 is a square.at n=18A385810