312500

Appears in sequences

• a(0) = 1; a(n) = 4*5^(n-1) for n >= 1.at n=8A005054
• a(n) = Product_{i=0..7} floor((n+i)/8).at n=39A009694
• Numbers of form 5^i*10^j, with i, j >= 0.at n=28A025625
• a(n) = 5*a(n-2), starting 1,2,4.at n=16A026395
• Triangle whose (i,j)-th entry is binomial(i,j)*5^(i-j)*5^j.at n=24A038247
• Numbers k such that the sum of 2nd, 3rd, 4th and 5th powers of divisors of k are divisible by sum of divisors of k.at n=21A074632
• Numbers n such that the period length P(n) of the Fibonacci sequence mod n is a multiple of n.at n=41A105953
• a(1)=5. For n > 1, a(n) = 4*5^(n-1) = A005054(n).at n=7A110595
• Number of palindromes of length n (in base 5).at n=14A117857
• Number of palindromes of length n (in base 5).at n=15A117857
• a(n) = (n^3 - n^2)*5^n.at n=4A128988
• 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=15A133632
• 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=31A140730
• Triangle interpolating between the subsets of an n-set (A000079) and the trees on n labeled nodes (A000272) (read by rows).at n=24A154715
• a(n) = 5*a(n-2) for n > 2; a(1) = 4, a(2) = 5.at n=14A163141
• Numbers with prime signature {7,2}, i.e., of form p^7*q^2 with p and q distinct primes.at n=18A179689
• a(n) = phi(n^4).at n=24A189393
• Triangle read by rows, T(n,k) = k^n*A056040(n), n>=0, 0<=k<=n.at n=26A195009
• a(n) = n^8 - n^7.at n=5A240931
• Numbers k such that the k-th cyclotomic polynomial has a root mod 5.at n=23A245478