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A290725
Numbers with 3k digits for some k such that the first k digits minus the middle k digits equals the last k digits.
2
101, 110, 202, 211, 220, 303, 312, 321, 330, 404, 413, 422, 431, 440, 505, 514, 523, 532, 541, 550, 606, 615, 624, 633, 642, 651, 660, 707, 716, 725, 734, 743, 752, 761, 770, 808, 817, 826, 835, 844, 853, 862, 871, 880, 909, 918, 927, 936, 945, 954, 963, 972, 981, 990, 100010, 100109, 100208, 100307
OFFSET
1,1
LINKS
EXAMPLE
987654333 is a member because 987-654=333.
MAPLE
N:= 100: # to get the first N terms
count:= 0:
Res:= NULL:
for d from 1 while count < N do
for x1 from 10^(d-1) to 10^d-1 while count < N do
for x2 from 0 to x1 while count < N do
x3:= x1 - x2;
count:= count+1;
Res:= Res, x1*10^(2*d)+x2*10^d+x3;
od od od:
Res; # Robert Israel, Aug 09 2017
MATHEMATICA
kd3Q[n_]:=Module[{c=FromDigits/@Partition[IntegerDigits[n], IntegerLength[ n]/3]}, c[[1]]-c[[2]]==c[[3]]]; Table[Select[Range[10^(3n-1), 10^(3n)-1], kd3Q], {n, 2}]//Flatten (* Harvey P. Dale, Feb 25 2020 *)
CROSSREFS
A286846 is a subsequence.
Sequence in context: A259300 A025349 A025341 * A255966 A305396 A266717
KEYWORD
nonn,base
AUTHOR
N. J. A. Sloane, Aug 09 2017
EXTENSIONS
More terms from Robert Israel, Aug 09 2017
STATUS
approved