18530

Appears in sequences

• Numbers n such that 105*2^n-1 is prime.at n=36A050578
• Number of collinear triples in a 3 X n rectangular grid.at n=34A057566
• a(n) = floor(n^4/64).at n=33A060494
• a(1)=0, and a(n+1) is the position of first occurrence of a(n) in the decimal expansion of 1/Pi.at n=22A098319
• a(n) = 16n^2 + n.at n=33A157474
• a(n) = 64*n^2 + 2*n.at n=17A158070
• a(n) = 1156*n^2 + 34.at n=4A158731
• 5 times centered pentagonal numbers: 5*(5*n^2 + 5*n + 2)/2.at n=38A164015
• Numbers that can be represented as a sum of two distinct nontrivial prime powers in three or more ways.at n=19A225104
• Euler's fearsome foursome.at n=0A229076
• Numbers k that are the product of four distinct primes such that x^2+y^2 = k has integer solutions.at n=30A248712
• T(n,k)=Number of nXk arrays containing k copies of 0..n-1 with every element equal to or 1 greater than any north or northeast neighbors modulo n and the upper left element equal to 0.at n=58A267553
• Number of nX(n+4) arrays of permutations of n+4 copies of 0..n-1 with every element equal to or 1 greater than any north or northeast neighbors modulo n and the upper left element equal to 0.at n=3A267557
• Number of 4Xn arrays containing n copies of 0..4-1 with every element equal to or 1 greater than any north or northeast neighbors modulo 4 and the upper left element equal to 0.at n=7A267558
• The least common multiple of 1+n and 1+n^2.at n=33A281660
• a(n) = n*(2*(n - 2)*n + (-1)^n + 3)/4.at n=34A323724
• Numbers k such that the k-th composition in standard order is an alternating permutation of {1..k} for some k.at n=31A349051
• Squarefree integers k such that x^4 - k*y^2 = 1 has a nontrivial solution.at n=31A356496