A327545 Triangle T(n,k) read by rows giving the number of zeroless polydivisible numbers in base n that have k distinct digits with 1 <= k <= n-1.
1, 4, 0, 5, 2, 2, 10, 14, 8, 0, 7, 14, 20, 2, 2, 26, 39, 84, 60, 27, 0, 11, 47, 108, 95, 63, 3, 3, 20, 101, 233, 369, 289, 79, 17, 0, 19, 86, 306, 475, 714, 409, 146, 1, 1, 32, 201, 979, 2048, 3581, 3474, 1925, 449, 51, 0, 17, 114, 507, 1273, 2224, 2239, 1074, 230, 35, 0, 0
Offset: 2
Examples
n | zeroless polydivisible numbers in base n --+------------------------------------------ 2 | [1] 3 | [1, 2, 11, 22] 4 | [1, 2, 3, 22, 222], [12, 32], [123, 321] So T(2,1) = 1, T(3,1) = 4, T(3,2) = 0, T(4,1) = 5, T(4,2) = 2, T(4,3) = 2. Triangle begins: n\k | 1 2 3 4 5 6 7 8 9 -----+---------------------------------------- 2 | 1; 3 | 4, 0; 4 | 5, 2, 2; 5 | 10, 14, 8, 0; 6 | 7, 14, 20, 2, 2; 7 | 26, 39, 84, 60, 27, 0; 8 | 11, 47, 108, 95, 63, 3, 3; 9 | 20, 101, 233, 369, 289, 79, 17, 0; 10 | 19, 86, 306, 475, 714, 409, 146, 1, 1;
Links
- Seiichi Manyama, Rows n = 2..18, flattened
- Wikipedia, Polydivisible number.
Crossrefs
Programs
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Ruby
def A(n) d = 0 a = (1..n - 1).map{|i| [i]} ary = [n - 1] + Array.new(n - 2, 0) while d < n - 2 d += 1 b = [] a.each{|i| (1..n - 1).each{|j| m = i.clone + [j] if (0..d).inject(0){|s, k| s + m[k] * n ** (d - k)} % (d + 1) == 0 b << m ary[m.uniq.size - 1] += 1 end } } a = b end ary end def A327545(n) (2..n).map{|i| A(i)}.flatten end p A327545(10)
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