A095410 Numbers n such that total number of decimal digits of all distinct prime factors of n equals the number of digits of n.

2, 3, 4, 5, 7, 8, 9, 10, 11, 12, 13, 14, 15, 17, 18, 19, 20, 21, 23, 24, 28, 29, 31, 35, 36, 37, 40, 41, 43, 45, 47, 48, 50, 53, 54, 56, 59, 61, 63, 67, 71, 72, 73, 75, 79, 80, 83, 89, 96, 97, 98, 101, 103, 104, 105, 106, 107, 109, 111, 113, 115, 116, 117, 118, 119, 120, 122

Offset: 1

Author

Labos Elemer, Jun 21 2004

Keywords

• base
• nonn

Examples

			n=184, 3 digits,prime set={2,23} also with 3 digits {2,2,3}.
		

Links

• Harvey P. Dale, Table of n, a(n) for n = 1..1000

Crossrefs

Cf. A055642, A095407, A095408, A095409, A095411.

Programs

Mathematica

ffi[x_] :=Flatten[FactorInteger[x]] lf[x_] :=Length[FactorInteger[x]] ba[x_] :=Table[Part[ffi[x], 2*j-1], {j, 1, lf[x]}] tdp[x_] :=Flatten[Table[IntegerDigits[Part[ba[x], j]], {j, 1, lf[x]}], 1] pl[x_] :=Length[tdp[x]] nl[x_] :=Length[IntegerDigits[x]] t1=Table[nl[w], {w, 1, 1000}];t2=Table[pl[w], {w, 1, 1000}];t2-t1 Flatten[Position[t2-t1, 0]]
Rest[Select[Range[200],Length[Flatten[IntegerDigits/@Transpose[ FactorInteger[ #]][[1]]]]==IntegerLength[#]&]] (* Harvey P. Dale, Oct 22 2011 *)

Formula

Solutions to A095407[x]=A055642[x].