20097

Appears in sequences

• a(n) = n*(n+5)*(n+6)*(n+7)/24.at n=22A005587
• Number of compositions of n into 6 ordered relatively prime parts.at n=16A023031
• Triangles in open triangular matchstick arrangement (triangle minus one side) of side n.at n=43A045947
• Partial sums of second pentagonal numbers with even index (A049453).at n=21A051895
• Average of three successive primes squared, (prime(n)^2+prime(n+1)^2+prime(n+2)^2)/3, n>=3.at n=30A075893
• Array read by antidiagonals, giving the sizes pi_l(c_l(m,n)) of minimal covers (see reference for precise definition).at n=49A133713
• Row l=7 of array in A133713.at n=4A133717
• Column 4 of array in A133713.at n=5A133719
• Column 5 of triangle in A133721.at n=30A133724
• Column 6 of triangle in A133721.at n=37A133733
• Numbers n = concat(a,b) such that phi(n) = phi(a) * phi(b), where phi = A000010.at n=32A147619
• Numerator of Euler(n, 7/16).at n=4A156527
• Wiener index of the n-sunlet graph.at n=30A180574
• Number of (n+1)X3 0..2 arrays with every 2X2 subblock trace equal to some horizontal or vertical neighbor 2X2 subblock trace.at n=2A185838
• Number of (n+1)X4 0..2 arrays with every 2X2 subblock trace equal to some horizontal or vertical neighbor 2X2 subblock trace.at n=1A185839
• T(n,k)=Number of (n+1)X(k+1) 0..2 arrays with every 2X2 subblock trace equal to some horizontal or vertical neighbor 2X2 subblock trace.at n=7A185845
• T(n,k)=Number of (n+1)X(k+1) 0..2 arrays with every 2X2 subblock trace equal to some horizontal or vertical neighbor 2X2 subblock trace.at n=8A185845
• The Wiener index of the ortho-polyphenyl chain with n hexagons (see the Dou et al. and the Deng references).at n=10A216108
• Expansion of 1/(1 - x + x^2 - x^3 - x^6 - x^9 + x^10 - x^11 + x^12).at n=51A225499
• 40-gonal numbers: a(n) = 38*n*(n-1)/2 + n.at n=33A261191