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Numbers that are not of the form m + (sum of base-100 digits of m).
2

%I #16 Oct 30 2024 21:43:03

%S 1,3,5,7,9,11,13,15,17,19,21,23,25,27,29,31,33,35,37,39,41,43,45,47,

%T 49,51,53,55,57,59,61,63,65,67,69,71,73,75,77,79,81,83,85,87,89,91,93,

%U 95,97,99,200,301,402,503,604,705,806,907,1008,1109

%N Numbers that are not of the form m + (sum of base-100 digits of m).

%C Sum of base-100 digits of m can also be described as "break the digit-string of m into pairs starting at the right, and add these 2-digit numbers". For example, 12345 -> 45 + 23 + 1 = 69.

%e Sum of pairs of digits of 12345 = 45 + 23 + 1 = 69.

%e The terms of this sequence can be found with a sieve:

%e n = 1 to 99 --> doubling --> 2, 4, 6, 8, 10, ..., 196, 198

%e n = 100 to 199 --> 101, 103, 105, ... , 199, 201, ... , 297, 299

%e n = 200 to 299 --> 202, 204, 206, 208, ... , 398, 400

%e n = 300 to 303 --> 303, 305, 307, 309

%e n = 1 to 303 (sorted) --> 2, 4, 6, ..., 96, 98, 100, 101, 102, 103, ..., 197, 198, 199, 201, 202, 203, 204, 205, ...,297, 298, 299, 300, 302, 303, 304, 305, 306, 307, 308, 309, 310, 312, 314, 316, 318, 320, 322, ..., 398, 400

%e The numbers < 304 that are missing are the terms of this sequence: 1, 3, 5, 7, ..., 97, 99, 200, 301

%Y This is a base-100 analog of A003052.

%K nonn,base

%O 1,2

%A _Peter Weiss_, Feb 26 2017