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A242226
Numbers that can be written as a sum of numbers using only nonzero decimal digits in ascending order.
3
45, 54, 63, 72, 81, 90, 99, 108, 117, 126, 135, 144, 153, 162, 171, 180, 189, 198, 207, 216, 225, 234, 252, 261, 270, 279, 288, 315, 324, 333, 342, 378, 387, 396, 432, 441, 450, 459, 486, 495, 504, 513, 549, 558, 567, 576, 594, 603, 612, 621, 630, 666
OFFSET
1,1
COMMENTS
The sequence is divisible by 9 and contains 187 terms. The first term is 45 = 1+2+...+9, the last term is 1+23456789 = 23456790.
The decomposition is not unique, for example 666 = 1+2+3+4+567+89 = 123+456+78+9.
LINKS
EXAMPLE
45 = 1+2+3+4+5+6+7+8+9;
54 = 12+3+4+5+6+7+8+9;
63 = 1+23+4+5+6+7+8+9;
72 = 1+2+34+5+6+7+8+9;
81 = 1+2+3+45+6+7+8+9 = 12+34+5+6+7+8+9;
90 = 1+2+3+4+56+7+8+9 = 12+3+45+6+7+8+9;
99 = 1+2+3+4+5+67+8+9 = 12+3+4+56+7+8+9 = 1+23+45+6+7+8+9.
MAPLE
g:= proc(i, j) option remember;
`if`(i=j, {i}, {parse(cat(seq(h, h=i..j))),
seq(seq(seq(x+y, y=g(h+1, j)), x=g(i, h)), h=i..j-1)})
end:
sort([(g(1, 9) minus {123456789})[]])[]; # Alois P. Heinz, May 09 2014
CROSSREFS
Cf. A008591.
Sequence in context: A345482 A295802 A242267 * A335375 A039423 A043246
KEYWORD
nonn,base,fini,full
AUTHOR
Michel Lagneau, May 08 2014
STATUS
approved