%I
%S 0,1,2,3,4,5,6,7,8,9,11,12,14,15,21,22,23,24,25,26,32,33,35,36,41,42,
%T 44,45,47,48,51,52,53,54,55,56,57,58,59,62,63,65,66,68,69,70,74,75,77,
%U 78,80,84,85,86,87,88,89,90,95,96,98,99,111,112,114,115,121,122,123,124
%N Numbers which are "easy" to key on a standard telephone keypad.
%C On a standard telephone keypad, i.e. 123  456  789  0, a number is "easy" to key in if each adjacent pair of digits in the number are the same, or are adjacent  either horizontally or vertically or diagonally. For example, adjacent to the 2 key are 1 and 3 (horizontal), 5 (vertical) and 4 and 6 (diagonal) so any of these digits could come after a 2 (but not 7, 8, 9 or 0).
%H N. J. A. Sloane, <a href="/A124097/b124097.txt">Table of n, a(n) for n = 1..10001</a>
%e 126 is a term since the 1 and 2 keys are adjacent and the 6 is diagonally adjacent to the 2.
%K nonn,dumb,base
%O 1,3
%A _Paul Richards_, Dec 12 2006
