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A143712 Numbers with at least two digits in which all digits except the rightmost are even and the rightmost is odd. 2
21, 23, 25, 27, 29, 41, 43, 45, 47, 49, 61, 63, 65, 67, 69, 81, 83, 85, 87, 89, 201, 203, 205, 207, 209, 221, 223, 225, 227, 229, 241, 243, 245, 247, 249, 261, 263, 265, 267, 269, 281, 283, 285, 287, 289, 401, 403, 405, 407, 409, 421, 423, 425, 427, 429, 441, 443, 445, 447 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
These are called e-type numbers, cf. A163396.
LINKS
MATHEMATICA
Select[Range[21, 500], (id = IntegerDigits[#1]; And @@ EvenQ /@ Most[id] && OddQ[Last[id]]) & ] (* Jean-François Alcover, May 23 2013 *)
eodQ[n_]:=Module[{td=TakeDrop[IntegerDigits[n], -1]}, OddQ[td[[1, 1]]]&&AllTrue[ td[[2]], EvenQ]]; Select[Range[10, 500], eodQ] (* Harvey P. Dale, Aug 06 2022 *)
CROSSREFS
Sequence in context: A095451 A169887 A007929 * A163396 A169903 A095447
KEYWORD
nonn,base
AUTHOR
STATUS
approved

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Last modified April 18 20:26 EDT 2024. Contains 371781 sequences. (Running on oeis4.)