26097
domain: N
Appears in sequences
- Numbers k such that k and 5*k, taken together, are pandigital.at n=17A115925
- a(n) is the number of central ideals of a garland of order 2n, i.e., a(n) = g(2n,n), where g(n,k) is the number of ideals of size k in a garland (or double fence) of order n (see A137278).at n=14A136029
- G.f.: exp( Sum_{n>=1} (x^n/n) * Product_{d|n} (1 + d*x^n) ).at n=42A205478
- Number of active (ON, black) cells at stage 2^n-1 of the two-dimensional cellular automaton defined by "Rule 718", based on the 5-celled von Neumann neighborhood.at n=7A273426
- a(n) = a(n-1) + 3*a(n-2) -2*a(n-3) - 2*a(n-4), where a(0) = 0, a(1) = 0, a(2) = 2, a(3) = 3.at n=19A295857
- Numbers k such that the largest prime divisor of k^4+1 is less than k.at n=34A309562
- Number of meanders of length n with Motzkin-steps avoiding the consecutive steps UD, HH and DU.at n=16A329665