51424

Appears in sequences

• a(n) is least k such that k and 10k are anagrams in base n (written in base 10).at n=22A023102
• Numbers having four 7's in base 9.at n=18A043484
• G.f. = continued fraction: A(x) = 1/(1-x-x^2/(1-x^3-x^4/(1-x^5-x^6/(1-x^7-x^8/(...))))).at n=20A088352
• Numbers n such that 9*10^n + 5*R_n - 4 is prime, where R_n = 11...1 is the repunit (A002275) of length n.at n=21A103100
• Number of binary strings of length n with equal numbers of 00011 and 00101 substrings.at n=17A164229
• Poincaré series for hyperbolic reflection group with Coxeter diagram shown in Comments.at n=17A265053
• Triangle T(n,r) read by rows: order of the semigroup of orientation-preserving partial transformations of n elements with breath r.at n=44A289710
• The order of the semigroup of orientation-preserving full transformations on n elements.at n=7A289715
• Number of 2-matchings of the n-th centered square grid graph.at n=9A344679
• Numbers k such that k, k + 1 and k + 2 are 3 consecutive Niven (Harshad) numbers that are also divisible by a square.at n=5A359839
• Coefficient of x^n in the expansion of 1/( (1-x)^2 * (1-x^2)^3 )^n.at n=6A370270