19089

Appears in sequences

• Dimensions of the Jordan operad.at n=7A001776
• Expansion of e.g.f. theta_3^(-9/2).at n=4A015685
• Numbers k such that sigma(k) = sigma(k+6).at n=39A015866
• a(n) = s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n+1-k), where k = [ (n+1)/2 ], s = (1, p(1), p(2), ...), t = (composite numbers).at n=37A024480
• a(n) = s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n-k+1), where k = [ n/2 ], s = (1, p(1), p(2), ...), t = (composite numbers).at n=36A025100
• Numbers k such that 5^k - 4 is prime.at n=9A059613
• Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 01000-11111-00010 pattern in any orientation.at n=18A147015
• Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, -1), (-1, -1, 1), (0, 1, -1), (1, 0, 1)}.at n=11A148172
• Numbers n which are concatenations n=x//y such that x^2+y^3 is a multiple of n.at n=35A162464
• Triangle read by rows: T(n,k) (n >= 1, 1 <= k <= n) = number of alternating anagrams on n letters (of length 2n) which are decomposable into at most k components.at n=31A239895
• Number of maximal classes determined by permutations.at n=9A246069
• Number of n X 4 0..1 arrays with no element unequal to more than four of its king-move neighbors and with new values introduced in order 0 sequentially upwards.at n=4A281951
• Number of nX5 0..1 arrays with no element unequal to more than four of its king-move neighbors and with new values introduced in order 0 sequentially upwards.at n=3A281952
• T(n,k)=Number of nXk 0..1 arrays with no element unequal to more than four of its king-move neighbors and with new values introduced in order 0 sequentially upwards.at n=31A281955
• T(n,k)=Number of nXk 0..1 arrays with no element unequal to more than four of its king-move neighbors and with new values introduced in order 0 sequentially upwards.at n=32A281955
• Dirichlet convolution of the integer partition numbers A000041 with the number of divisors function A000005.at n=36A323766
• a(n) is the sum of the Wieferich and Wall-Sun-Sun residues of prime(n).at n=25A339639
• Dirichlet g.f.: Product_{k>=2} (1 + k^(-s))^(k^2).at n=47A343322
• a(n) = Sum_{j=1..n} Sum_{i=1..n} (j mod i).at n=43A367379
• Expansion of (1/x) * Series_Reversion( x/(x+1/(1+x^3)) ).at n=16A370837