18449

Appears in sequences

• Numbers k where cos(k) decreases monotonically to 0.at n=29A046957
• Numbers k where sin(k) increases monotonically to 1 (or cosec(k) decreases).at n=33A046959
• Composite numbers whose divisors (except 1) all contain the digit 9.at n=34A062680
• Non-palindromic n and its digit reversal have the same sum of prime factors (with repetition).at n=39A085607
• a(n) = (9 + 14*n + 12*n^2 + 4*n^3)/3.at n=23A166911
• Number of 4X2 integer matrices with each row summing to zero, row elements in nondecreasing order, rows in lexicographically nondecreasing order, and the sum of squares of the elements <= 2*n^2 (number of collections of 4 zero-sum 2-vectors with total modulus squared not more than 2*n^2, ignoring vector and component permutations).at n=31A192703
• Floor(AGM(n^2, n^3)), where AGM denotes the arithmetic-geometric mean.at n=39A234362
• Non-palindromic composite numbers such that n' = [Rev(n)]', where n' is the arithmetic derivative of n.at n=11A259077
• Numbers m such that A338038(m) = A338038(A004086(m)) where A004086(i) is i read backwards and A338038(i) is the sum of the primes and exponents in the prime factorization of i ignoring 1-exponents; palindromes and multiples of 10 are excluded.at n=34A338039