A143712 - OEIS

A143712

Numbers with at least two digits in which all digits except the rightmost are even and the rightmost is odd.

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

Harvey P. Dale, Table of n, a(n) for n = 1..1000

Index entries for sequences related to carryless arithmetic

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

Cf. A144162, A163396, A169984.

Sequence in context: A095451 A169887 A007929 * A163396 A375214 A169903

Adjacent sequences: A143709 A143710 A143711 * A143713 A143714 A143715

KEYWORD

nonn,base

AUTHOR

David Applegate, Marc LeBrun and N. J. A. Sloane, Aug 24 2010

STATUS

approved