19847

Appears in sequences

• Numbers k that, when expressed in base 6 and then interpreted in base 9, give a multiple of k.at n=16A062939
• a(n) is the least k such that for any p prime dividing n, p does not divide binomial((n+1)*k, k+1), or -1 if no such k exists.at n=11A075833
• Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 1), (-1, 1, 1), (1, 0, -1), (1, 0, 1), (1, 1, -1)}.at n=8A149422
• Smallest number x such that sigma(x) = sigma(x(n)), where x(n) is the n-th arithmetic derivatives of x and x is not equal to x(n).at n=10A246774
• Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 473", based on the 5-celled von Neumann neighborhood.at n=29A272425
• Numbers k such that (19*10^k + 77) / 3 is prime.at n=23A276353
• Expansion of (x+x^3+x^5)/(1-x-3*x^3-x^5).at n=17A309331
• a(n) = prime(n) * prime(2n).at n=23A319613
• Nonprime Heinz numbers of multiples of triangular partitions, or of finite arithmetic progressions with offset 0.at n=32A325407