26810

Appears in sequences

• a(n) = (2*n-1)*(5*n^2-5*n+2)/2.at n=17A063495
• 47-gonal numbers.at n=34A095311
• a(n) = n*(n+1)*(20*n-17)/6.at n=20A172117
• Number of lower triangles of a 3 X 3 0..n array with each element differing from all of its diagonal, vertical, antidiagonal and horizontal neighbors by two or less.at n=26A195249
• Sum of all the middle parts in the partitions of 3n into 3 parts.at n=34A236364
• a(n) = n*(n + 1)*(n^2 - n + 3)/6.at n=20A257055
• Numbers k such that Bernoulli number B_{k} has denominator 4686.at n=21A295770
• G.f.: Sum_{k>=1} x^(2*k)/(1+x^(2*k)) * Product_{k>=1} 1/(1-x^k).at n=36A305121
• Number of n X n 0..1 arrays with every element unequal to 2, 3, 4, 6 or 7 king-move adjacent elements, with upper left element zero.at n=4A305169
• Number of nX5 0..1 arrays with every element unequal to 2, 3, 4, 6 or 7 king-move adjacent elements, with upper left element zero.at n=4A305172
• T(n,k)=Number of nXk 0..1 arrays with every element unequal to 2, 3, 4, 6 or 7 king-move adjacent elements, with upper left element zero.at n=40A305175
• Number of 6-regular bipartitions of n.at n=21A328548
• Number of ways to write n as an ordered sum of 5 prime powers (including 1).at n=44A341134
• Weird untouchable numbers.at n=14A357326