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A067284 a(n) = number of integers k such that k is not of the form m + reverse(m) for any m (cf. A067031) and A067030(n) occurs in the 'Reverse and Add' trajectory of k. 5

%I #6 Mar 30 2012 17:27:34

%S 1,1,1,1,1,1,1,1,1,1,1,2,3,5,5,8,7,12,9,1,13,21,14,1,6,11,1,4,14,1,2,

%T 9,1,2,1,2,1,22,1,2,1,2,2,3,2,3,2,3,2,16,2,3,3,5,3,4,3,5,3,4,3,30,4,6,

%U 5,5,4,6,5,5,4,6,15,8,6,6,5,8,6,6,5,8,6,9,24,7,6,9,8,7,6,9,7,12,9,8,20

%N a(n) = number of integers k such that k is not of the form m + reverse(m) for any m (cf. A067031) and A067030(n) occurs in the 'Reverse and Add' trajectory of k.

%C For an integer j not in A067030 there exists no integer k of the form m + reverse(m) such that j occurs in the trajectory of k. a(n) >= A067032(n); A067737 gives the terms of A067030 such that a(n) > A067032(n). A067288 gives the records in this sequence, A067287 gives the terms of A067030 at which these records are attained.

%H <a href="/index/Res#RAA">Index entries for sequences related to Reverse and Add!</a>

%e a(14) = 5, since A067030(14) = 55 and the five integers 7, 23, 32, 41, 50 are not of the form m + reverse(m) for any m and 55 occurs in the trajectory of each of them. a(25) = 11, since A067030(25) = 154 and the eleven integers 1, 25, 34, 43, 52, 59, 61, 68, 70, 86, 95 are not of the form m + reverse(m) for any m and 154 occurs in the trajectory of each of them.

%Y Cf. A067030, A067031, A067032, A067287, A067288, A067737.

%K base,nonn

%O 0,12

%A _Klaus Brockhaus_, Feb 04 2002

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