20135

Appears in sequences

• a(n) = number of compositions of n in which the maximum part size is 4.at n=17A000102
• Numbers k such that 6*k+1, 6*k+7, 6*k+13, 6*k+19 are consecutive primes.at n=22A090839
• First entry of the vector v(n), where v(0) is the 2 by 2 column vector [0,1], v(n)=(M(n-1)^(n-1))v(n-1) and M(k) is the 2 x 2 matrix [[0,1],[1,k]].at n=5A105065
• a(n) = prime(n) * prime(n+2) - 2 * prime(n+1).at n=32A152532
• Number of nondecreasing arrangements of 5 numbers in -(n+3)..(n+3) with sum zero and not more than two numbers equal.at n=17A188238
• Number of palindromic Carlitz compositions of n.at n=37A239327
• Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 629", based on the 5-celled von Neumann neighborhood.at n=25A273297
• Duplicate of A090839.at n=22A296055
• a(1) = 1; a(n+1) = Sum_{d|n, n/d odd} a(d)^(n/d).at n=43A307780
• Number of integer compositions of n into parts that are alternately equal and unequal.at n=37A357643