292681

Appears in sequences

• Smallest square that contains the digits of n in its exact middle.at n=26A062689
• Numbers n such that sigma(d(n^3))==d(sigma(n^2)), where d(n) is the number of divisors of n.at n=34A063797
• Smallest composite k such that phi(k) > k*(1-1/n^2).at n=22A069639
• Odd squares not in A113659.at n=18A103962
• a(n) = A000670(n)^2.at n=5A122725
• Numbers k such that sigma(k)-k-1 divides sigma(k+1)-k-2, where sigma(k) is sum of positive divisors of k and the ratio is greater than zero.at n=5A132585
• a(1)=1. a(n) = the smallest integer > a(n-1) such that |d(a(n)) - d(a(n-1))| = n-1, where d(m) = the number of positive divisors of m.at n=19A139695
• Square array, read by antidiagonals: form the Euler-Seidel matrix for the sequence {2^k*k!} and then divide column k by 2^k*k!.at n=39A143411
• Numbers k of the form q^2, q = prime, such that k-2 is a prime.at n=35A146981
• Squares which are anagrams of cubes.at n=24A161860
• Larger prime power associated with record gap in A167186.at n=25A167189
• Squares in A111153.at n=28A175255
• Composite numbers with both 10 and -10 as primitive root.at n=23A218766
• Number of n X 2 0..2 arrays with rows, antidiagonals and columns unimodal.at n=8A223719
• Lucky numbers that are prime powers.at n=38A225322
• Prime powers (A025475) representable as (p+q)/2, where p and q are distinct prime powers.at n=32A225388
• E.g.f. C(x) satisfies: C(x)^2 - S(x)^2 = 1 and D(x)^4 - S(x)^4 = 1, where functions S(x) and D(x) are described by A280625 and A280627, respectively.at n=5A280626
• E.g.f. C(x) + S(x), such that: C(x)^2 - S(x)^2 = 1 and D(x)^4 - S(x)^4 = 1, where functions S(x), C(x), and D(x) are described by A280625, A280626, and A280627, respectively.at n=10A280628
• Lexicographically first sequence of positive squares, no two or more of which sum to a square.at n=14A305884
• Numbers k such that A206369(k) is prime.at n=43A383649