Find the smallest positive integer N such that a concatenation of N and 2*N
is a pandigital number.
30729 has this feature, but it is not the smallest number.
starting with the smallest:
N 2N
13485 26970
13548 27096
13845 27690
14538 29076
14685 29370
14835 29670
14853 29706
14865 29730
15486 30972
16485 32970
18546 37092
18645 37290
20679 41358
20769 41538
20793 41586
23079 46158
26709 53418
26907 53814
27069 54138
27093 54186
27309 54618
29067 58134
29073 58146
29307 58614
30729 61458
30792 61584
30927 61854
31485 62970
32079 64158
32709 65418
32907 65814
34851 69702
35148 70296
35481 70962
38145 76290
38451 76902
45138 90276
45186 90372
45381 90762
46185 92370
46851 93702
48135 96270
48351 96702
48513 97026
48516 97032
48531 97062
48615 97230
48651 97302
DefDbl A-Z
Dim crlf$
Private Sub Form_Load()
Form1.Visible = True
Text1.Text = ""
crlf = Chr$(13) + Chr$(10)
For n = 10000 To 99999
DoEvents
ns$ = LTrim(Str(n))
good = 1
For i = 2 To Len(ns)
If InStr(ns, Mid(ns, i, 1)) < i Then good = 0: Exit For
Next
If good Then
n2 = 2 * n
checkstr$ = ns + LTrim(Str(n2))
For i = 2 To Len(checkstr)
If InStr(checkstr, Mid(checkstr, i, 1)) < i Then good = 0: Exit For
Next
If good Then
Text1.Text = Text1.Text & ns & " " & n2 & crlf
End If
End If
Next
Text1.Text = Text1.Text & crlf & " done"
End Sub
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Posted by Charlie
on 2015-12-14 19:06:38 |
All of them
