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

%I A061385 #14 Mar 17 2023 11:11:06
%S A061385 2,13,22,31,40,105,114,123,132,141,150,204,213,222,231,240,303,312,
%T A061385 321,330,402,411,420,501,510,600,1007,1016,1025,1034,1043,1052,1061,
%U A061385 1070,1106,1115,1124,1133,1142,1151,1160,1205,1214,1223,1232,1241,1250,1304
%N A061385 Numbers n such that sum of digits = twice number of digits.
%H A061385 Robert Israel, <a href="/A061385/b061385.txt">Table of n, a(n) for n = 1..10000</a>
%e A061385 141 is a term as the arithmetic mean of the digits is (1+4+1)/3 = 2.
%p A061385 S:= proc(d,k,flag) option remember;
%p A061385   if d = 1 then
%p A061385     if k >= 0 and k <= 9 then return [k]
%p A061385     else return []
%p A061385     fi
%p A061385   fi;
%p A061385   [seq(op(map(`+`, procname(d-1,k-i,0), i*10^(d-1))),i=flag..min(k,9))]
%p A061385 end proc:
%p A061385 seq(op(S(d,2*d,1)),d=1..5); # _Robert Israel_, Apr 23 2017
%o A061385 (Magma) [ n: n in [1..1310] | &+Intseq(n) eq 2*#Intseq(n) ];  // _Bruno Berselli_, Jun 30 2011
%Y A061385 Cf. A061383, A061384, A061386, A061387, A061388, A061423, A061424, A061425.
%K A061385 nonn,base,easy
%O A061385 1,1
%A A061385 _Amarnath Murthy_, May 03 2001
%E A061385 More terms from Larry Reeves (larryr(AT)acm.org), May 16 2001