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.
Sequence of sets of n-digit numbers that are weakly polydivisible and strictly pandigital is (with A = 10):
{0}
{1}
{12}
{123,321}
{}
{}
{123654,321654}
{}
{38165472}
{381654729}
{381654729A}
Triangle is:
{1}
{1,2}
{1,2,3}
{3,2,1}
{1,2,3,6,5,4}
{3,2,1,6,5,4}
{3,8,1,6,5,4,7,2}
{3,8,1,6,5,4,7,2,9}
{3,8,1,6,5,4,7,2,9,10}
polyQ[q_]:=And@@Table[Divisible[FromDigits[Take[q,k]],k],{k,Length[q]}];
Flatten[Table[Select[Permutations[Range[n]],polyQ],{n,8}]]
a(2) = 123 is in the sequence, because in base 4, 12[4]=6 is divisible by 2 and 123[4] = 27 = A235164(2) is divisible by 3. The same is the case for 321, where 32[4]=14 is even and 321[4] = 57 = A235164(3) is divisible by 3. For the 9-digit term 381654729, the initial digits are to be interpreted in base 10: 38, 318, ..., 381654729 are divisible by 2, 3, ..., 9, respectively.
for(n=1,9,p=vector(n,i,(n+1)^(i-1));for(k=0,n!-1,d=numtoperm(n,k);for(j=2,n,sum(i=1,j,d[i]*p[j-i+1])%j &&next(2)); print1(Vec(d)*vector(n,i,10^(n-i))~", ")))
The terms with 5 digits in base 6 are 2285 = 14325[6] and 7465 = 54321[6], since these numbers are divisible by 5, and 14[6] = 10, 143[6] = 63, 1432[6] = 380 are divisible by 2, 3 and 4, respectively, and the same is the case for 54[6] = 34, 543[6] = 207 and 5432[6] = 1244.
for(n=1,9,p=vector(n,i,(n+1)^(i-1));for(k=0,n!-1,d=numtoperm(n,k);for(j=2,n,sum(i=1,j,d[i]*p[j-i+1])%j &&next(2)); print1(d*vector(n,i,(n+1)^(n-i))~",")))
def vgen(n,b):
if n == 1:
t = list(range(1,b))
for i in range(1,b):
u = list(t)
u.remove(i)
yield i, u
else:
for d, v in vgen(n-1,b):
for g in v:
k = d*b+g
if not k % n:
u = list(v)
u.remove(g)
yield k, u
A235164_list = [a for n in range(2,15,2) for a, b in vgen(n-1,n)] # Chai Wah Wu, Jun 07 2015
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