28280

Appears in sequences

• First diagonal of A027516.at n=16A027519
• Numbers k such that 13*2^k+1 is prime.at n=10A032356
• Revert transform of (1 + x - 2x^2 + x^3)/(1 + 2x).at n=12A049144
• Numbers k such that k | sigma_13(k) - phi(k)^13.at n=21A055707
• Growth series for Heisenberg group.at n=26A063810
• Triangle read by rows: T(n,0)=1, T(n,n)=(2*n-1)!!+1, T(n,k) = 2*(n-k) * T(n-1,k-1) + 2*(k+1)*T(n-1,k).at n=23A099755
• a(n) = binomial(n,4) - binomial(floor(n/2),4) - binomial(ceiling(n/2),4).at n=31A111385
• Sum[k=0..n] Eulerian[n,k]*n^k.at n=4A122020
• a(n) = 36*n^2 + 2*n.at n=27A158064
• E.g.f.: 4*exp(4*x) / (5 - exp(4*x)).at n=5A201368
• s(k)-s(j), where the pairs (k,j) are given by A205852 and A205853, and s(k) denotes the (k+1)-st Fibonacci number.at n=35A205854
• s(k)-s(j), where the pairs (k,j) are given by A205862 and A205863, and s(k) denotes the (k+1)-st Fibonacci number.at n=32A205864
• s(k)-s(j), where the pairs (k,j) are given by A205867 and A205868, and s(k) denotes the (k+1)-st Fibonacci number.at n=35A205869
• s(k)-s(j), where the pairs (k,j) are given by A205877 and A205878, and s(k) denotes the (k+1)-st Fibonacci number.at n=18A205879
• Number of (w,x,y) with all terms in {0,...,n} and w != x and x < range(w,x,y).at n=40A212970
• Rhonda numbers in sexagesimal number system.at n=11A255731
• Sum over all partitions lambda of n into 3 distinct parts of Product_{i:lambda} prime(i).at n=13A258358
• Expansion of r(q^5) / r(q)^5 in powers of q where r() is the Rogers-Ramanujan continued fraction.at n=36A285585
• Decimal representation of the diagonal from the corner to the origin of the n-th stage of growth of the two-dimensional cellular automaton defined by "Rule 502", based on the 5-celled von Neumann neighborhood.at n=29A288766
• G.f.: Sum_{k>=0} x^(k^2) * Product_{j=1..k} 1/(1 - x^j)^4.at n=19A376712