23577

Appears in sequences

• q-factorial numbers 3!_q.at n=28A069778
• p(p^2-p+1) as p runs through the primes.at n=9A083558
• a(0) = 0, a(1) = a(2) = 1, a(3) = 2, a(4) = 4, a(5) = 8, a(6) = 16, for n>5: a(n+1) = SORT[ a(n) + a(n-1) + a(n-2) + a(n-3) + a(n-4) + a(n-5) + a(n-6)], where SORT places digits in ascending order and deletes 0's.at n=40A108567
• a(1) = 1 then the least multiple of odd numbers not odd multiples of 5, (3,7,9,11,13,17,19,21,23,27,29,...) such that every partial concatenation is noncomposite.at n=34A110433
• a(n) = nonnegative value y such that (A155135(n), y) is a solution to the Diophantine equation x^3+28*x^2 = y^2.at n=30A155137
• a(n) = nonnegative value y such that (A155136(n), y) is a solution to the Diophantine equation x^3+28*x^2 = y^2.at n=29A155138
• The number of permutations of length n sortable by 3 prefix reversals (in the pancake sorting sense).at n=29A228398
• 60-gonal (hexacontagonal) numbers: a(n) = n(29n - 28).at n=29A249911
• a(n) = m is the least m = b*c > a(n-1) such that (b+c)*n = m-1 where 1 < b <= c < m.at n=27A364171
• a(n) = Sum_{k=1..n} sigma_2( n/gcd(k,n) ).at n=28A372226