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A061385
Numbers n such that sum of digits = twice number of digits.
7
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
1,1
LINKS
EXAMPLE
141 is a term as the arithmetic mean of the digits is (1+4+1)/3 = 2.
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
PROG
(Magma) [ n: n in [1..1310] | &+Intseq(n) eq 2*#Intseq(n) ]; // Bruno Berselli, Jun 30 2011
KEYWORD
nonn,base,easy
AUTHOR
Amarnath Murthy, May 03 2001
EXTENSIONS
More terms from Larry Reeves (larryr(AT)acm.org), May 16 2001
STATUS
approved