21098
domain: N
Appears in sequences
- For n>0, a(n) is the least quasi-Carmichael number to base -n, extended to n=0 with the least composite squarefree integer.at n=16A029591
- Smallest multiple of n with property that each digit is one less (mod 10) than the previous digit; or 0 if no such multiple exists.at n=11A062399
- Smallest multiple of n with property that each digit is one less (mod 10) than the previous digit; or 0 if no such multiple exists.at n=22A062399
- Number of primes between n^5 and (n+1)^5.at n=15A062517
- Ordered product of the sides of primitive Pythagorean triangles divided by 60.at n=26A081752
- a(n) = 1 + (26*n+17+7*n^2)*n/2.at n=17A095796
- Smallest available integer which fits into the repeating pattern 9876543210.at n=42A098756
- Triangle T(n,k)read by rows given by [3,1,3,1,3,1,3,1,3,1,3,1,...] DELTA [1,0,0,0,0,0,0,0,...] where DELTA is the operator defined in A084938.at n=40A133366
- Triangle T(n,k) with the coefficient [x^k] of the polynomial p(n,x) in row n, column k, where p(n,x) = x*p(n-1,x)-n^2*p(n-2,x).at n=50A136448
- Start with 0; then add one to each single digit.at n=38A158699
- a(n) = smallest k having at least four prime divisors d such that (d + n) | (k + n).at n=15A202159
- Composite squarefree numbers n such that p+d(n) divides n+d(n), where p are the prime factors of n and d(n) the number of divisors of n.at n=0A228299
- Even Quasi-Carmichael numbers.at n=3A262252
- Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 566", based on the 5-celled von Neumann neighborhood.at n=37A272989
- Number of n X n 0..1 arrays with every element equal to 0, 1, 2, 3, 4 or 5 king-move adjacent elements, with upper left element zero.at n=3A298964
- Number of nX4 0..1 arrays with every element equal to 0, 1, 2, 3, 4 or 5 king-move adjacent elements, with upper left element zero.at n=3A298966
- T(n,k)=Number of nXk 0..1 arrays with every element equal to 0, 1, 2, 3, 4 or 5 king-move adjacent elements, with upper left element zero.at n=24A298970