A045816 Number of times the digits are repeated in A045815.
1, 1, 1, 1, 1, 1, 1, 1, 1, 4, 8, 4, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 6
Offset: 1
Examples
Divisors of 20345 are (1,20345), the numbers of digits are [0(1),1(1),2(1),3(1),4(1),5(1)], so a(1) = 1. Divisors of 45050 are (1,2,3,10,4505,13414,22323,45050), the numbers of digits (0-5) are [0(4),1(4),2(4),3(4),4(4),5(4)], so a(10) = 4.
Links
- Naohiro Nomoto, In the list of divisors of n,...
Programs
-
Maple
isA045816 := proc(n) local c,j,b,h,a ; a := [0,0,0,0,0,0] : c := numtheory[divisors](n): for j from 1 to nops(c) do b := convert(c[j], base, 6); for h from 1 to nops(b) do a[b[h]+1] := a[b[h]+1]+1: end do: end do: if(a[1]=a[2] and a[2]=a[3] and a[3]=a[4] and a[4]=a[5] and a[5]=a[6]) then a[1] ; else -1 ; end if: end: n := 1: while true do a := isA045816(n) : if a >= 0 then printf("%d, ",a) ; fi ; n := n+1 : od : # R. J. Mathar, Jun 26 2007
Extensions
More terms from Sean A. Irvine, Sep 26 2011