28098

Appears in sequences

• Numbers whose base-5 representation contains exactly three 3's and three 4's.at n=28A045307
• Values of m such that N=(am+1)(bm+1)(cm+1) is a 3-Carmichael number (A087788), where a,b,c = 1,2,11.at n=9A064242
• Number of squares (of another matrix) in the group GL(2,Z_n) described in sequence A000252.at n=24A068516
• Numbers n such that 5*10^n + 8*R_n - 7 is prime, where R_n = 11...1 is the repunit (A002275) of length n.at n=12A103022
• Triangle read by rows: T(n,k) is the number of permutations of {1,2,...,n} having k up-down cycles (0<=k<=n). A cycle (b(1), b(2), ...) is said to be up-down if, when written with its smallest element in the first position, it satisfies b(1)<b(2)>b(3)<... .at n=49A186358
• Numbers k such that k is the average of four consecutive primes k-11, k-1, k+1 and k+11.at n=25A259025
• Inverse Euler transform of Thue-Morse sequence A001285.at n=36A316149
• a(n) = ((n + 1) - 9*(n + 1)^2 + 8*(n + 1)^3)/6.at n=27A331987
• Triangle read by rows, T(n, k) = A000670(n) * binomial(n, k).at n=22A362585
• Triangle read by rows, T(n, k) = A000670(n) * binomial(n, k).at n=26A362585