120409

Appears in sequences

• a(n) = (11*n + 6)^2.at n=31A017462
• a(n) = (12*n + 11)^2.at n=28A017654
• Numbers k such that sigma(k)*phi(k) is squarefree.at n=29A065299
• Perfect powers pp(n) with perfect power index n.at n=27A075433
• Squares of primes of the form 4*k+3.at n=35A087691
• Numbers m such that Sum_{p prime|m} p^r(p) = m, where r(p) is the least positive primitive root of p (A001918).at n=34A101051
• Squares of lesser of twin primes.at n=20A108570
• Smallest nontrivial perfect power with same leading digits as n!.at n=4A109685
• Squares of the form 5p - 6, where p is prime.at n=18A110481
• Ulam numbers that are perfect squares.at n=39A173545
• Squares in A111153.at n=18A175255
• Numbers n such that (the sum of the divisors of n) plus (the sum of the squares of the divisors of n) plus (the sum of the cubes of the divisors of n) is a prime number.at n=15A220586
• Number of nX6 arrays of occupancy after each element moves to some horizontal or antidiagonal neighbor, with every occupancy equal to zero or two.at n=5A221380
• T(n,k)=Number of nXk arrays of occupancy after each element moves to some horizontal or antidiagonal neighbor, with every occupancy equal to zero or two.at n=60A221381
• Perfect powers m^k such that m, k and m+k are primes.at n=23A258400
• Numbers n such that the number of digits d in n is not prime and for each factor f of d the sum of the d/f digit groupings of size f is a square.at n=8A258660
• Compact numbers: numbers that can be expressed more compactly using their prime factorization than their decimal expansion.at n=27A279070
• Expansion of e.g.f. exp(sec(x)*exp(x) - 1).at n=8A305710
• Numbers k such that phi(k) == 2 (mod 12), where phi is the Euler totient function (A000010).at n=34A332511
• The position of the first n in A339895.at n=40A339897