31173

Appears in sequences

• Numbers n such that 261*2^n-1 is prime.at n=34A050889
• Expansion of 1/sqrt(1-2*x-7*x^2+8*x^3).at n=10A098477
• Primefree centuries (i.e., numbers k such that no prime exists between 100*k and 100*k+99).at n=2A181098
• Number of partitions of n minus the number of primes <= n.at n=38A183151
• Number of (n+1) X 2 0..2 arrays with rows and columns in nondecreasing order and with no 2 X 2 subblock sum differing from a horizontal or vertical neighbor subblock sum by more than one.at n=10A184073
• Number of 0..n arrays x(0..3) of 4 elements with nondecreasing average value.at n=20A200764
• Number of length n+2 0..6 arrays with the sum of second differences multiplied by some arrangement of +-1 equal to zero.at n=3A250559
• T(n,k)=Number of length n+2 0..k arrays with the sum of second differences multiplied by some arrangement of +-1 equal to zero.at n=39A250561
• Number of length 4+2 0..n arrays with the sum of second differences multiplied by some arrangement of +-1 equal to zero.at n=5A250563
• Number of nX5 0..1 arrays with every element equal to 0, 1 or 3 horizontally or antidiagonally adjacent elements, with upper left element zero.at n=6A301881
• Number of 7Xn 0..1 arrays with every element equal to 0, 1 or 3 horizontally or antidiagonally adjacent elements, with upper left element zero.at n=4A301890
• Number of inversion sequences of length n avoiding the consecutive pattern 100.at n=8A328441
• Numbers k such that A176972(k) = 7^k + 7*k + 1 is prime.at n=6A370664