A095785 Values of n for which A095777(n) is 16 (those terms which are expressible in decimal digits for bases 2 through 17, but not for base 18).

17, 105, 289, 294, 902, 903, 904, 905, 918, 919, 5491, 5492, 5493, 5508, 5525, 16905, 16920, 16921, 270354, 271665, 271700, 271701, 275205, 275256, 3342391, 3342392, 3342405, 3342408, 3342409, 3342421, 3342422, 3342423, 3342424, 3342425, 3342438, 3342439

Offset: 1

Author

Chuck Seggelin (seqfan(AT)plastereddragon.com), Jun 05 2004

Keywords

• base
• nonn

Examples

			a(5)=902 because 902 when expressed in successive bases starting at 2 will produce its first non-decimal digit at base 18. Like so: 1110000110, 1020102, 32012, 12102, 4102, 2426, 1606, 1212, 902, 750, 632, 545, 486, 402, 386, 321. In base 18, 902 is 2E2.
		

Crossrefs

Cf. A095777.

Programs

Maple

S := []; for n from 1 to 15000 do; if 1>0 then; ct := 0; ok := true; b := 2; if (n>9) then; while ok=true do; L := convert(n, base, b); for e in L while ok=true do; if (e > 9) then ok:=false; fi; od; if ok=true then; ct := ct + 1; b := b + 1; fi; od; fi; if ct=16 then S := [op(S), n]; fi; fi; od; S;

Mathematica

b18Q[n_]:=Module[{idn=Table[IntegerDigits[n,b],{b,2,18}]},Max[Flatten[Most[ idn]]]<10 && Max[Last[idn]]>9]; Select[Range[50000],b18Q] (* Harvey P. Dale, Feb 09 2013 *)

Extensions

More terms from Harvey P. Dale, Feb 09 2013