A127273 Numbers n such that sum of the digits of n and of n+1 divides n + (n+1), n >= 1.
1, 2, 3, 4, 5, 6, 7, 8, 10, 13, 22, 31, 40, 52, 67, 73, 94, 100, 103, 104, 112, 121, 123, 130, 136, 142, 148, 161, 175, 180, 199, 202, 203, 211, 218, 220, 232, 237, 240, 256, 262, 275, 283, 294, 301, 302, 310, 314, 322, 325, 337, 351, 364, 391, 400, 401, 412, 418
Offset: 1
Examples
Sum of the digits of 52 and 53 is 7+8 = 15, which divides 52+53 = 105 = 7*15. Hence 52 is a term. Sum of the digits of 9 and 10 is 9+1 = 10, which does not divide 9+10 = 19. Hence 9 is not in the sequence.
Programs
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Mathematica
Select[ Range[ 325 ], Mod[ 2#+1, Apply[ Plus, IntegerDigits[ # ] ]+Apply[ Plus, IntegerDigits[ #+1 ] ] ]==0& ] - Farideh Firoozbakht
Extensions
Edited, corrected and extended by Klaus Brockhaus and Farideh Firoozbakht, Mar 29 2007