A030149 Even palindromes in which parity of digits alternates.
0, 2, 4, 6, 8, 212, 232, 252, 272, 292, 414, 434, 454, 474, 494, 616, 636, 656, 676, 696, 818, 838, 858, 878, 898, 21012, 21212, 21412, 21612, 21812, 23032, 23232, 23432, 23632, 23832, 25052, 25252, 25452, 25652, 25852, 27072, 27272, 27472
Offset: 1
Links
- Giovanni Resta, Table of n, a(n) for n = 1..10000
Programs
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Mathematica
altQ[n_] := n < 10 || Union[Total /@ Partition[ Mod[ IntegerDigits@ n, 2], 2, 1]] == {1}; palQ[n_] := Block[{d = IntegerDigits[n]}, d == Reverse@ d]; Select[2 Range[0, 15000], palQ[#] && altQ[#] &] (* Giovanni Resta, Aug 16 2018 *)
Extensions
a(1) = 0 prepended and offset changed by Giovanni Resta, Aug 16 2018