cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A127273 Numbers n such that sum of the digits of n and of n+1 divides n + (n+1), n >= 1.

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%I A127273 #4 Mar 31 2012 10:22:32
%S A127273 1,2,3,4,5,6,7,8,10,13,22,31,40,52,67,73,94,100,103,104,112,121,123,
%T A127273 130,136,142,148,161,175,180,199,202,203,211,218,220,232,237,240,256,
%U A127273 262,275,283,294,301,302,310,314,322,325,337,351,364,391,400,401,412,418
%N A127273 Numbers n such that sum of the digits of n and of n+1 divides n + (n+1), n >= 1.
%e A127273 Sum of the digits of 52 and 53 is 7+8 = 15, which divides 52+53 = 105 = 7*15. Hence 52 is a term.
%e A127273 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.
%t A127273 Select[ Range[ 325 ], Mod[ 2#+1, Apply[ Plus, IntegerDigits[ # ] ]+Apply[ Plus, IntegerDigits[ #+1 ] ] ]==0& ] - Farideh Firoozbakht
%K A127273 nonn,base
%O A127273 1,2
%A A127273 _J. M. Bergot_, Mar 27 2007
%E A127273 Edited, corrected and extended by _Klaus Brockhaus_ and _Farideh Firoozbakht_, Mar 29 2007