19590
domain: N
Appears in sequences
- Numbers k such that sigma(k)+1 is a square and sets a new record for such squares.at n=36A063729
- Sum of primes p with n^2 < p < (n+1)^2.at n=39A108314
- Triangle read by rows: T(n,k) is the number of Motzkin paths of length n having k UDH's starting at level 0 (U=(1,1),H=(1,0),D=(1,-1)).at n=41A114581
- Sum of the n-th primorial and the n-th compositorial number.at n=10A117733
- a(n) = 196*n^2 - n.at n=9A158003
- a(n) = 784*n^2 - 2*n.at n=4A158398
- a(n) = 100*n^2 - 10.at n=13A158490
- Expansion of x*(1+2*x+8*x^2+4*x^3+3*x^4) / ( (1+x)^2*(x-1)^4 ).at n=29A178947
- Number of (w,x,y,z) with all terms in {1,...,n} and w*x>=3*y*z.at n=17A211919
- A213784/12.at n=31A213789
- a(n) is the conjectured highest power of n which has no four identical digits in succession.at n=1A216065
- a(n) = n * Sum_{d|n} binomial(d+2,3)/d.at n=44A343544
- Number of n-element unlabeled disconnected N-free posets.at n=9A349367
- Partial sums of A071619.at n=44A358042