84135

Appears in sequences

• Numbers n such that (i) the sum of the distinct primes dividing n is divisible by the largest prime dividing n and (ii) n has exactly 4 distinct prime factors and (iii) n is squarefree.at n=31A071143
• a(n+1) is the integer part of sqrt(2*a(n)^2).at n=31A102822
• Numbers which are both lucky and pentagonal.at n=18A128511
• Numbers n such that product of double factorials of the digits of n equals sigma(n).at n=20A158989
• Runs of consecutive numbers with the same number and sum of divisors.at n=15A225758
• Numbers k that divide sigma(k) - sigma(k-1).at n=30A227307
• Numbers k such that sigma(k) = sigma(k-1).at n=22A231546
• E.g.f.: 1 / (1 + x + Sum_{k>=2} prime(k-1) * x^k / k!).at n=10A346791
• Pentagonal numbers which are products of four distinct primes.at n=39A381919