27823

Properties

Appears in sequences

• Total number of prime power parts in all partitions of n.at n=29A073335
• Lenny Conundrum #168: Neopet species in alphabetical order, converted to digits by the phone keypad code.at n=4A119568
• Numbers n such that (22^n - 1)/21 is prime.at n=8A127997
• Primes p of Erdos-Selfridge class 4+ with largest prime factor of p+1 not of class 3+.at n=22A129472
• Number of n X n binary arrays symmetric under horizontal reflection with all ones connected only in a 1000-1110-0111-0001 pattern in any orientation.at n=13A147398
• Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 219", based on the 5-celled von Neumann neighborhood.at n=34A270932
• The number of hanging vertically stable self-avoiding walks of length n on a 2D square lattice where only the connecting rods have mass.at n=15A335596
• a(n) = number of nonempty subsets S of {1,2,...,n} such that (number of primes in S) <= (number of nonprimes in S).at n=15A369781
• Prime numbersat n=3039