19111

Appears in sequences

• Molien series for complete weight enumerator of self-dual code over GF(5) containing all-1's vector.at n=19A028345
• Numbers with multiplicative digital root value 9.at n=29A034056
• Number of numbers k which give 1 after applying exactly n iterations of the 3k+1 algorithm (if a number is even, divide it by 2; if it is odd, multiply by 3 and add 1). This total includes numbers k which also give 1 for a smaller number of iterations (i.e., for this sequence we do not assume the algorithm halts when 1 is reached).at n=41A082538
• Smallest k such that |M(k)| = n^2, where M(x) is Mertens's function A002321.at n=6A084234
• a(n) = ceiling(((1*n^0 + 1*n^1 + 2*n^2 + 4*n^3)/(1*n^0 + 2*n^1 + 1*n^2))^2).at n=35A085505
• Near-repunit semiprimes.at n=33A105993
• Pyramid game person numbers that have integer solutions.at n=24A135051
• Composite numbers whose multiplicative digital root is 9.at n=23A201024
• Volume of elliptic cone (rounded down) with semi-minor axis = height = n and semi-major axis = 3*n/2.at n=22A228391
• Composites in base 10 that remain composite in exactly four bases b, 2 <= b <= 10, expansions interpreted as decimal numbers.at n=10A256354
• Coefficients in Molien series for 5-dimensional faithful representation of Horrocks-Mumford group G_{HM}.at n=38A258702
• Semiprimes that are the sum of the first n odd primes for some n.at n=28A274182
• Numbers using only digits 1 and 9.at n=38A284294
• a(n) = [x^(n^3)] Product_{k=1..n} Sum_{m>=0} x^(k^2*m).at n=6A321239
• Positions of 0's in A330314.at n=17A330325
• a(n) = Sum_{k=0..n} sigma(k^2 + 1), where sigma(k) is the sum of divisors of k (A000203).at n=34A333172
• Expansion of Sum_{k>0} x^(2*k)/(1+x^k)^5.at n=25A363613