21715

Appears in sequences

• Powers of cube root of 20 rounded down.at n=10A018033
• Powers of cube root of 20 rounded to nearest integer.at n=10A018034
• a(n) = T(n, n-5), array T as in A055818.at n=13A055822
• Numbers k > 1 such that, in base 6, k and k^2 contain the same digits in the same proportion.at n=6A061660
• Numbers k such that sopf(k) = sopf(k+2), where sopf(k) = A008472(k).at n=20A063968
• a(n) = A002861(n) + A000081(n).at n=11A124682
• Numbers k such that k and k^2 use only the digits 1, 2, 4, 5 and 7.at n=16A136989
• Shifts 8 places left under Euler transform with a(0)=0 and a(n)=1 for n<8.at n=35A218025
• Number of 2 X n arrays of the minimum value of corresponding elements and their horizontal or diagonal neighbors in a random, but sorted with lexicographically nondecreasing rows and nonincreasing columns, 0..3 2 X n array.at n=12A219940
• a(n) = ceiling(n^3*(Pi/2)).at n=23A248198
• 26-gonal numbers: a(n) = n*(12*n-11).at n=43A255185
• Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 435", based on the 5-celled von Neumann neighborhood.at n=30A272151
• Number of 5-element subsets of [n] having a prime element sum.at n=23A320680
• Consecutive states of the linear congruential pseudo-random number generator (625*s + 6571) mod 31104 when started at s=1.at n=6A385279