25020

Appears in sequences

• a(n) = Sum_{k=0..2n} (k+1) * A027052(n, 2n-k).at n=9A027076
• n satisfying sigma(n+1) = sigma(n-1).at n=30A055574
• Occurrences of most frequently occurring number in 1-to-n 5-dimensional multiplication table.at n=29A057344
• Occurrences of most frequently occurring number in 1-to-n 5-dimensional multiplication table.at n=30A057344
• Numbers k such that sigma(k-1) divides sigma(k+1).at n=36A067130
• Square root of a(n) contains the n-th Fibonacci number as a string of digits to the immediate right of the decimal point (excluding leading zeros).at n=21A099401
• Numbers n such that 3*10^n-7 is prime.at n=14A102964
• Numbers k such that k and k^2 use only the digits 0, 2, 4, 5 and 6.at n=59A136898
• Expansion of (4*x^2+x-1)/(12*x^3+4*x^2+x-1).at n=10A147833
• a(n) = 1000*n + 20.at n=24A157510
• Numbers n such that sigma(n+1) - sigma(n-1) = k*n for some integer k, where sigma(n) = A000203 (sum of divisors of n).at n=31A223137
• Smallest number k such that prime(n) divides the n-th divisor of k.at n=32A226101
• Numbers k such that sigma(k+1) divides sigma(k-1).at n=31A227304
• Numbers k whose nearest neighbors have the same number of divisors, the same number of distinct prime factors, and the same sum of divisors.at n=10A294173