cp's OEIS Frontend

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.

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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.

Original entry on oeis.org

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
Offset: 1

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Comments

These are called e-type numbers, cf. A163396.

Crossrefs

Programs

  • 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 *)
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