 All about flooble | fun stuff | Get a free chatterbox | Free JavaScript | Avatars  perplexus dot info  Factorials & factorions (Posted on 2015-10-19) A factorion is a number that equals the sum of the factorials of its decimal digits, e.g. 145 is a factorion because 1! + 4! + 5! = 1 + 24 + 120 = 145.

There are exactly four (in base 10) such numbers;
1, 2, 145, and the last one is for you to find.

Bonus task: Determine all numbers such that the sum of factorials of their digits - expressed in any imaginable base- is exactly the same regardless of the base chosen. Comments: ( Back to comment list | You must be logged in to post comments.) computer solution | Comment 1 of 2
1
2
145
40585

DefDbl A-Z
Dim crlf\$, fact(9)

Form1.Visible = True

Text1.Text = ""
crlf = Chr\$(13) + Chr\$(10)

fact(0) = 1
For i = 1 To 9
fact(i) = i * fact(i - 1)
Next

For n = 1 To 9999999
ns\$ = LTrim(Str(n))
tot = 0
For i = 1 To Len(ns)
tot = tot + fact(Val(Mid(ns, i, 1)))
Next
If tot = n Then
Text1.Text = Text1.Text & n & crlf
End If
DoEvents
Next n

Text1.Text = Text1.Text & crlf & " done"

End Sub

 Posted by Charlie on 2015-10-19 14:42:49 Please log in:

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