18735

Appears in sequences

• Positive numbers k such that k and 2*k are anagrams in base 9 (written in base 9).at n=31A023079
• a(n) = Sum_{k=0..n} T(n,k), T given by A026758.at n=13A026765
• Number of partitions in parts not of the form 17k, 17k+1 or 17k-1. Also number of partitions with no part of size 1 and differences between parts at distance 7 are greater than 1.at n=47A035962
• Becomes prime or 4 after exactly 9 iterations of f(x) = sum of prime factors of x.at n=11A048131
• Number of permutations satisfying -k<=p(i)-i<=r and p(i)-i not in I, i=1..n, with k=2, r=3, I={0,2}.at n=19A080006
• Number of compositions of n with either all parts odd or all parts even.at n=21A097896
• 45-gonal numbers: n*(43*n-41)/2.at n=29A098924
• Members of 3-cycles of permutation A111273.at n=14A113701
• Ulam's spiral (SSE spoke).at n=34A143839
• Binomial transform of A012245 (characteristic function of factorial numbers).at n=18A143963
• Numbers k such that 24 plus the k-th triangular number is a perfect square.at n=9A154150
• Number of reduced words of length n in Coxeter group on 6 generators S_i with relations (S_i)^2 = (S_i S_j)^6 = I.at n=6A163922
• Number of binary strings of length n with equal numbers of 00000 and 01001 substrings.at n=15A164184
• Numbers whose squares have 2R-1 digits, such that the number represented by leftmost R digits and number represented by rightmost R digits divide each other evenly.at n=15A216233
• Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 139", based on the 5-celled von Neumann neighborhood.at n=30A270280
• Number of 1-dimensional sandpiles with n grains piling up against the wall.at n=21A291896
• Number of compositions of n such that every subsequence has a different sum.at n=45A335357
• Number of distinct sums i^3 + j^3 + k^3 for 0<=i<=j<=k<=n.at n=48A374710