18487

Appears in sequences

• Expansion of 1/((1-3x)*(1-6x)*(1-8x)).at n=4A017932
• Strong pseudoprimes to base 97.at n=18A020323
• Numbers n such that n and n-1 are differences between 2 positive cubes in at least one way.at n=18A038595
• Number of partitions satisfying cn(1,5) <= cn(2,5) + cn(3,5) and cn(4,5) <= cn(2,5) + cn(3,5).at n=39A039890
• Numbers k such that the number of primes <= k is equal to the sum of primes from the smallest prime factor of k to the largest prime factor of k.at n=7A074210
• a(n) = (6*n+1)*(6*n+7).at n=22A085026
• Largest number k such that k^2 divides A007781(6n+1).at n=38A127854
• Triangle read by rows: T(n, k) = (n-k)^n - n*k*(n-k) + k^n, with T(0, 0) = 1.at n=31A129821
• Triangle read by rows: T(n, k) = (n-k)^n - n*k*(n-k) + k^n, with T(0, 0) = 1.at n=32A129821
• Least k such that the difference between consecutive 3-almost primes A014612(k) equals n, or 0 if no such k exists.at n=25A131939
• Products of three distinct happy primes A035497.at n=26A154717
• Number of strings of numbers x(i=1..4) in 0..n with sum i*x(i) equal to n*4.at n=43A184704
• Number of partitions of 3n into at most 5 parts.at n=26A256525
• a(n) = Sum_{i=1..n} (prime(i+1)-prime(i))*prime(n+1-i).at n=47A343531
• Coefficient of x^n in the expansion of ( (1-x+x^3) / (1-x) )^n.at n=14A372413
• Centered hexagonal numbers that are sphenic numbers.at n=6A382628