A061424 Sum of digits = 7 times number of digits.

7, 59, 68, 77, 86, 95, 399, 489, 498, 579, 588, 597, 669, 678, 687, 696, 759, 768, 777, 786, 795, 849, 858, 867, 876, 885, 894, 939, 948, 957, 966, 975, 984, 993, 1999, 2899, 2989, 2998, 3799, 3889, 3898, 3979, 3988, 3997, 4699, 4789, 4798, 4879, 4888, 4897

Offset: 1

Author

Amarnath Murthy, May 03 2001

Keywords

• nonn
• base
• easy

Examples

			498 is a term as the arithmetic mean of the digits is (4+9+8)/3 = 7.
		

Links

• Robert Israel, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A061383-A061388, A061423-A061425.

Programs

Maple

filter:= proc(n) local L;
  L:= convert(n,base,10);
  convert(L,`+`)=nops(L)*7
end proc:
select(filter, [$1..10000]); # Robert Israel, Dec 07 2020

Mathematica

Select[Range[5000],Total[IntegerDigits[#]]==7IntegerLength[#]&] (* Harvey P. Dale, Oct 22 2022 *)

Extensions

More terms from Larry Reeves (larryr(AT)acm.org), May 16 2001

Offset changed by Robert Israel, Dec 07 2020