53010

Appears in sequences

• Numbers n such that 2*p(n)+3, 2*p(n+1)+3, 2*p(n+2)+3 are consecutive primes, where p(i) denotes the i-th prime.at n=32A088066
• Triangle read by rows: T(n,k) is the number of permutations p of [n] such that the length of the longest 2-stack sortable initial segment of p is equal to k.at n=42A094785
• Composite numbers such that the square root of the sum of squares of their prime factors is a prime.at n=21A134607
• Half the number of n X n symmetric binary matrices with no element unequal to a strict majority of its diagonal and antidiagonal neighbors.at n=6A190655
• Irregular triangle read by rows: T(n,k) (n >= 1, 0 <= k <= n^2) = number of n X n (0,1) real matrices with k zeros and permanent zero.at n=54A260043
• a(n) = n*(n + 7)*(n + 14)*(n + 21)/24.at n=24A264447
• Coordination sequence for (3,3,4) tiling of hyperbolic plane.at n=28A265071
• Number of ways to write n as an ordered sum of 9 primes.at n=20A340965
• Those primitive elements of A337386 that have exactly one primitive nondeficient divisor (A006039).at n=20A341604
• a(n) is the smallest number k with exactly n of its divisors in A052294.at n=34A363463