A061385 Numbers n such that sum of digits = twice number of digits.

2, 13, 22, 31, 40, 105, 114, 123, 132, 141, 150, 204, 213, 222, 231, 240, 303, 312, 321, 330, 402, 411, 420, 501, 510, 600, 1007, 1016, 1025, 1034, 1043, 1052, 1061, 1070, 1106, 1115, 1124, 1133, 1142, 1151, 1160, 1205, 1214, 1223, 1232, 1241, 1250, 1304

Offset: 1

Author

Amarnath Murthy, May 03 2001

Keywords

• nonn
• base
• easy

Examples

			141 is a term as the arithmetic mean of the digits is (1+4+1)/3 = 2.
		

Links

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

Crossrefs

Cf. A061383, A061384, A061386, A061387, A061388, A061423, A061424, A061425.

Programs

Magma

[ n: n in [1..1310] | &+Intseq(n) eq 2*#Intseq(n) ];  // Bruno Berselli, Jun 30 2011

Maple

S:= proc(d,k,flag) option remember;
  if d = 1 then
    if k >= 0 and k <= 9 then return [k]
    else return []
    fi
  fi;
  [seq(op(map(`+`, procname(d-1,k-i,0), i*10^(d-1))),i=flag..min(k,9))]
end proc:
seq(op(S(d,2*d,1)),d=1..5); # Robert Israel, Apr 23 2017

Extensions

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