19920

Appears in sequences

• a(n) = dot_product(1,2,...,n)*(4,5,...,n,1,2,3).at n=36A026040
• Denominators of continued fraction convergents to sqrt(299).at n=7A041563
• Number of homeomorphically irreducible multigraphs (or series-reduced multigraphs or multigraphs without nodes of degree 2) on 6 labeled nodes.at n=7A060536
• Numbers k such that sigma(k) - usigma(k) is a square and sets a new record for such squares.at n=24A063840
• Numbers k such that d(phi(k)) = phi(d(k)), where d=A000005 and phi=A000010.at n=33A078148
• Largest achievable determinant of a 4 X 4 matrix whose elements are 16 distinct integers chosen from the range -n...n.at n=1A097695
• The (1,1)-entry of the matrix M^n, where M is the 5 X 5 matrix [[0,1,0,0,0],[0,0,1,0,0], [0,0,0,1,0], [0,0,0,0,1], [1,0,-1,1,1]].at n=32A107293
• The result of the integration Integral_{t=0..oo} -rho*exp(-rho*s*t)*t^j*s*log(1+t) dt can be written as (F(u,j)*exp(u)*Ei(1,u) + G(u,j))/u^j, where rho>0, s>0, and u=rho*s. Sequence is the regular triangle corresponding to G(u,j).at n=41A121922
• a(n) = round( 2*Gamma(3 + n/3) + 2^(n/3) ).at n=16A133756
• Number of squarefree integers not exceeding 2^n.at n=15A143658
• Sum of primes between consecutive positive cubes.at n=7A158528
• Number of strictly increasing arrangements of 4 numbers in -(n+2)..(n+2) with sum zero.at n=42A188182
• Number of 2-cycle free city-block distance 1 permutations of a side-n hexagonal array.at n=2A216874
• Composition of the binomial transform of Fibonacci numbers and the Catalan transform of Fibonacci numbers.at n=8A219312
• Number of permutations of order n-1 such that no proper partial sum is zero modulo n.at n=8A232664
• Number of (n+2)X(n+2) 0..1 arrays with every 3X3 subblock sum of the two sums of the diagonal and antidiagonal minus the two sums of the central column and central row nondecreasing horizontally and vertically.at n=2A258518
• Number of (n+2)X(3+2) 0..1 arrays with every 3X3 subblock sum of the two sums of the diagonal and antidiagonal minus the two sums of the central column and central row nondecreasing horizontally and vertically.at n=2A258521
• T(n,k)=Number of (n+2)X(k+2) 0..1 arrays with every 3X3 subblock sum of the two sums of the diagonal and antidiagonal minus the two sums of the central column and central row nondecreasing horizontally and vertically.at n=12A258522
• Numbers k such that sigma(k) divides Fibonacci(k).at n=40A258748
• Terms of A143407, sorted.at n=40A270564