20504

Appears in sequences

• Numerators of approximations to e.at n=27A006258
• Smallest composite which when sum of prime factors is repeatedly subtracted reaches a prime after n iterations.at n=28A053093
• The next smallest pair of numbers is taken so that a(2n-1)/a(2n) converges to e = exp(1).at n=42A065370
• Number of ways to tile a 5 X 2n room with 1x2 Tatami mats. At most 3 Tatami mats may meet at a point.at n=35A068924
• Members of A000124 which are multiples of 11.at n=36A083511
• Multiples of 11 with digit sum 11, with no zero digits in odd places.at n=21A083512
• Sum of 1-fibits in Zeckendorf-expansion A014417(p) summed for all primes p in range ]2^n,2^(n+1)].at n=14A095336
• Numerators of "Farey fraction" approximations to e.at n=29A119014
• Transform of 1 by the T_{1,1} transformation (see link).at n=11A159328
• Number of binary strings of length n with no substrings equal to 0001 or 0100.at n=17A164394
• a(n) = Sum_{1 <= i < j <= n} F(i)*F(j), where F(k) is the k-th Fibonacci number.at n=10A190173
• Numbers n such that n^16+1 and (n+2)^16+1 are both prime.at n=29A217991
• Triangle read by rows: Number T(n,k) of 2-colored binary rooted trees with n nodes and exactly k <= n nodes of a specific color.at n=58A241555
• Triangle read by rows: Number T(n,k) of 2-colored binary rooted trees with n nodes and exactly k <= n nodes of a specific color.at n=62A241555
• Numbers with digit sum 11 that are multiples of 11.at n=30A283742
• The Padovan sequence A000931 doubled.at n=39A291289
• E.g.f.: A(x) + B(x) + C(x) where A'(x) = B(x)*C(x), B'(x) = A(x)*C(x), and C'(x) = A(x)*B(x), where A(x), B(x), and C(x) are the e.g.f.s of A292121, A292122, and A292123, respectively.at n=5A292120
• a(n) is the smallest m for which binomial(m,5) has exactly n distinct prime factors.at n=12A322158
• Number of integer partitions of n whose multiplicities have multiplicities that cover an initial interval of positive integers.at n=41A325330
• The number of edges on a vesica piscis formed by the straight line segments mutually connecting all vertices and all points that divide the sides into n equal parts.at n=11A342152