39062500

Appears in sequences

• a(0) = 1; a(n) = 4*5^(n-1) for n >= 1.at n=11A005054
• a(n) = 5*a(n-2), starting 1,2,4.at n=22A026395
• a(n)=(n-1)*n^(2*n).at n=4A086815
• a(1)=5. For n > 1, a(n) = 4*5^(n-1) = A005054(n).at n=10A110595
• Number of palindromes of length n (in base 5).at n=20A117857
• Number of palindromes of length n (in base 5).at n=21A117857
• a(1)=1, a(n) = (p-1)*a(n-1), if n is even, otherwise a(n) = p*a(n-2), where p = 5.at n=21A133632
• Squares n^2 whose decimal expansion contains n as a substring.at n=21A161783
• a(n) = 5*a(n-2) for n > 2; a(1) = 4, a(2) = 5.at n=20A163141
• Numbers k such that the sum of digits of k equals the concatenation of the distinct prime divisors of k.at n=9A212667
• Numbers k such that phi(sigma(k))/sigma(phi(k)) = 2.at n=29A229238
• a(n) = denominators of n!/10^n.at n=12A240534
• Numbers k such that the k-th cyclotomic polynomial has a root mod 5.at n=32A245478
• Integers k such that Sum_{i=1..t-1} d(i)/d(i+1) is prime, where d(1), ..., d(t) are the divisors of k in ascending order.at n=16A255576
• Integers that are one third of their arithmetic derivatives.at n=9A282771
• Squares k such that phi(k) is a cube.at n=21A358051
• Numbers with 11 odd divisors.at n=12A368950