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.
%I A029554 #14 May 21 2013 11:17:58
%S A029554 209,6409,9361,11713,12749,19721,21593,32509,50609,74269,85289,88559,
%T A029554 91793,99199,100529,152329,167977,187889,235049,271469,313049,471977,
%U A029554 742729,828529,841033,925129,1057793,1078649,1186949,1265609,1324609
%N A029554 Quasi-Carmichael numbers to base 9: squarefree composites n such that (n,2*3*5*7) = 1 and prime p|n ==> p-9|n-9.
%C A029554 If multiples of 2, 3, 5 and 7 are not excluded, then terms like 21, 33, 65, 77, 105, 165, 231,... belong to the sequence. - _Giovanni Resta_, May 21 2013
%H A029554 Giovanni Resta, <a href="/A029554/b029554.txt">Table of n, a(n) for n = 1..2091</a> (terms < 10^12)
%H A029554 <a href="/index/Ca#Carmichael">Index entries for sequences related to Carmichael numbers.</a>
%t A029554 qcm[n_, d_] := Block[{p, e}, {p, e} = Transpose@FactorInteger@n; Length[p] > 1 && Max[e] == 1 && d < Min[p] && And @@ IntegerQ /@ ((n - d)/(p - d))]; Select[Range[10^6], qcm[#, 9] &] (* _Giovanni Resta_, May 21 2013 *)
%K A029554 nonn
%O A029554 1,1
%A A029554 _David W. Wilson_