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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A328288 Triangle T(m,n) = # { k | concat(mk,nk) has no digit twice or more }, m >= n >= 0.

Original entry on oeis.org

0, 986409, 0, 438404, 304, 0, 572175, 153, 157, 0, 219202, 197, 124, 97, 0, 109601, 221, 156, 69, 171, 0, 255752, 73, 88, 142, 68, 69, 0, 140515, 129, 73, 81, 86, 62, 46, 0, 109601, 189, 88, 40, 67, 48, 51, 24, 0, 432645, 89, 80, 77, 31, 63, 68, 41, 20, 0, 0, 0, 132, 80, 90, 58, 32, 63, 99, 37, 0
Offset: 0

Views

Author

M. F. Hasler, Oct 10 2019

Keywords

Comments

This is an extended version of A328277 which is restricted to m > n >= 1.
One may consider T(m,n) defined for all m, n >= 0, which would yield a symmetric, infinite square array T(m,n), see formula.
For m and/or n = 0, see A328287(n) = T(0,n) = T(n,0), n >= 0.
The table is finite in the sense that T(m,n) = 0 for m > 987654321 (even if the multiple isn't pandigital, (mk, nk) cannot have more than 9+1 distinct digits), but also whenever the total number of digits of m and n exceeds 10.

Examples

			The table reads :
       0,    (m=0)
  986409, 0,      (m=1)
  438404, 304,   0,    (m=2)
  572175, 153, 157,   0,    (m=3)
  219202, 197, 124,  97,   0,   (m=4)
  109601, 221, 156,  69, 171,  0,   (m=5)
  255752,  73,  88, 142,  68, 69,  0,   (m=6)
  140515, 129,  73,  81,  86, 62, 46,  0,   (m=7)
  109601, 189,  88,  40,  67, 48, 51, 24,  0,   (m=8)
  432645,  89,  80,  77,  31, 63, 68, 41, 20,  0,   (m=9)
       0,   0, 132,  80,  90, 58, 32, 63, 99, 37,  0,   (m=10)
   90212,   0, 106,  69,  79, 50, 30, 45, 30, 38,  0,  0,    (m=11)
  127163,  76,   0,  96,  31, 62, 54, 27, 31, 49, 41, 27,   0,   (m=12)
   75768,  84,  72,   0,  31, 58, 47, 26, 23, 34, 43, 25, 20,   0,  (m=13)
   62436, 100,  64,  52,   0, 51, 44, 51, 42, 22, 38, 27, 18, 20   0,  (m=14)
  ...
The terms corresponding to T(2,1) = 304 and T(3,1) = 153 are given in Eric Angelini's post to the SeqFan list.
Column 0 is A328287 (number of multiples of m that have only distinct and nonzero digits).
		

Programs

Formula

T(m,n) = 0 whenever m == n (mod 10).
T(m,n) = T(n,m) for all m, n >= 0, if the condition m > n is dropped.