21239

Appears in sequences

• Retrograde trajectory of 13 under map n -> A132948(n).at n=41A132947
• Number of (n+4)X1 arrays of occupancy after each element moves up to +-4 places but not 0.at n=4A222551
• T(n,k)=Number of length (n+k)X1 arrays of occupancy after each element moves up to +-k places but not 0.at n=32A222555
• Minimal element in the primitive 3x-k cycle with the conjectured record-breaking maximal element A226683(n).at n=6A226685
• Least number k >= 0 such that (n!-k)/n is prime.at n=64A245696
• Numbers k such that 8k+1, 12k+1 and 24k+1 are primes and the last two are also of the form x^2 + 27y^2, so the tetrahedral number T(24k+1) is a Fermat pseudoprime to base 2.at n=12A321867
• Number of intervals in the lattice of Motzkin paths of length n.at n=8A379034