31328

Appears in sequences

• Numbers k that divide the (left) concatenation of all numbers <= k written in base 23 (most significant digit on left).at n=24A029492
• All 81 combinations of prefixing and following a(n) by a single digit are nonprime.at n=19A032734
• Composite numbers k such that all the decimal concatenations ik and ikj (i, j = 1...9) are also composite.at n=12A032737
• Jacobi form of weight 12 and index 1 for Niemeier lattice of type A_7^2 D_5^2.at n=7A055760
• Sum of a(n) terms of 1/k^(8/9) first exceeds n.at n=20A056185
• a(n) = 4*(3*n+1)*(3*n+2).at n=29A144410
• Nonsquarefree numbers such that n-1 is prime and n+1 is square.at n=39A146980
• Chromatic invariant of the n X n king graph.at n=3A295177
• G.f.: Sum_{n>=0} (1 + x*(1+x)^n)^n / 2^(n+1).at n=7A300279
• Expansion of Product_{k>=1} 1/(1 - x^k)^A000593(k).at n=20A301799
• Number of nX3 0..1 arrays with every element unequal to 0, 1, 2, 3, 5, 6 or 8 king-move adjacent elements, with upper left element zero.at n=6A317006
• Number of n X 7 0..1 arrays with every element unequal to 0, 1, 2, 3, 5, 6 or 8 king-move adjacent elements, with upper left element zero.at n=2A317010
• T(n,k)=Number of nXk 0..1 arrays with every element unequal to 0, 1, 2, 3, 5, 6 or 8 king-move adjacent elements, with upper left element zero.at n=38A317011
• T(n,k)=Number of nXk 0..1 arrays with every element unequal to 0, 1, 2, 3, 5, 6 or 8 king-move adjacent elements, with upper left element zero.at n=42A317011
• Indices of records in A327007.at n=11A327009
• Numbers k such that k and k+1 are both divisible by the number of their divisors over the Gaussian integers.at n=0A351852