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%I #12 Mar 10 2021 01:49:11
%S 2,22,242,24442,4204024,42044444024,4204486446844024,
%T 420448648888888846844024,42049644864886388888368846844694024
%N a(1) = 2, a(n) = smallest palindromic nontrivial multiple of a(n-1) containing all decimal digits of a(n-1).
%C Differs from A082777 at a(5). a(n) <= (10^A055642(a(n-1))+1)*a(n-1). If a(n-1) > 10 and the last digit of a(n-1) <= 4, then a(n) <= (10^(A055642(a(n-1))-1)+1)*a(n-1).
%e a(5) = 4204024 is a palindromic multiple of a(4) = 24442 and contains two '2' and three '4', all the digits of a(4).
%Y Cf. A055642, A082777.
%K nonn,base,more
%O 1,1
%A _Chai Wah Wu_, Mar 08 2021
%E a(9) from _Martin Ehrenstein_, Mar 10 2021