1562500

Appears in sequences

• a(0) = 1; a(n) = 4*5^(n-1) for n >= 1.at n=9A005054
• a(n) = Product_{i=0..8} floor((n+i)/9).at n=44A009714
• a(n+1) = floor(a(n)/2) * ceiling(a(n)/2), a(0) = 5.at n=6A014980
• Numbers of form 5^i*10^j, with i, j >= 0.at n=35A025625
• a(n) = 5*a(n-2), starting 1,2,4.at n=18A026395
• Smallest nontrivial extension of n-th cube which is a square.at n=24A030693
• Numerator of (n+1)^n/n!.at n=9A036505
• Squares which are the concatenation of two nonzero squares.at n=31A039686
• Numbers whose sum of exponents is equal to the product of prime factors.at n=19A071174
• Numbers k such that Sum_{i=1..k} gcd(k,i) divides Sum_{i=1..k} lcm(k,i).at n=23A072109
• Denominators of array in A089204.at n=44A089206
• a(1)=5. For n > 1, a(n) = 4*5^(n-1) = A005054(n).at n=8A110595
• Number of palindromes of length n (in base 5).at n=16A117857
• Number of palindromes of length n (in base 5).at n=17A117857
• 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=17A133632
• a(4*n)=5^n, a(4*n+1)=2*5^n, a(4*n+2)=3*5^n, a(4*n+3)=4*5^n.at n=35A140730
• a(n) = 4*n^4.at n=25A141046
• a(n) = 5*a(n-2) for n > 2; a(1) = 4, a(2) = 5.at n=16A163141
• Squares n with digit 1 that remain positive square after omitting all 1's from n.at n=24A176899
• Numbers of the form p^8*q^2 where p and q are distinct primes.at n=25A179699