20104

Appears in sequences

• Positive numbers k such that k and 2*k are anagrams in base 8 (written in base 8).at n=38A023073
• Numbers k such that k | sigma_11(k) - phi(k)^11.at n=14A055705
• Multiples of 7 whose sum of digits is equal to 7.at n=31A063416
• Number of initial odd numbers in class n of the iterated phi function.at n=35A092878
• Number of cycles of length 3 in the queen graph associated with an n X n chessboard.at n=14A144298
• Number of binary strings of length n with equal numbers of 00110 and 11001 substrings.at n=15A164256
• Number of n X 4 0..1 arrays avoiding 0 0 0 and 1 1 1 horizontally and 0 0 1 and 0 1 0 vertically.at n=6A207770
• T(n,k)=Number of nXk 0..1 arrays avoiding 0 0 0 and 1 1 1 horizontally and 0 0 1 and 0 1 0 vertically.at n=51A207774
• Number of 7Xn 0..1 arrays avoiding 0 0 0 and 1 1 1 horizontally and 0 0 1 and 0 1 0 vertically.at n=3A207777
• Number of intermediate configurations needed to be stored to calculate the number of ways in which a 9 X n grid can be tiled with triominoes.at n=3A215827
• Number of n X 5 0..1 arrays with no element equal to a strict majority of its king-move neighbors, with the exception of exactly one element, and with new values introduced in order 0 sequentially upwards.at n=4A279155
• T(n,k)=Number of nXk 0..1 arrays with no element equal to a strict majority of its king-move neighbors, with the exception of exactly one element, and with new values introduced in order 0 sequentially upwards.at n=40A279158
• Solution of the complementary equation a(n) = 4*a(n-2) + b(n-1), where a(0) = 1, a(1) = 3, b(0) = 2, and (a(n)) and (b(n)) are increasing complementary sequences.at n=13A295061
• Expansion of 1/(1 - x*(1 + x)^3)^2.at n=9A382613
• Triangle read by rows: number of permutations of length n that require exactly k removals from the beginning to become heapable.at n=38A390368