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A173203
a(n) is the smallest number which has in its English name the letter "e" in the n-th position beginning the count from the end, or -1 if no such number exists.
2
1, 3, 13, 7, 8, 11, 21, 17, 23, 74, 73, 104, 103, 111, 115, 113, 117, 124, 123, 173, 373, 723, 773, 873, 1103, 1111, 1115, 1113, 1117, 1124, 1123, 1173, 1323, 1373, 3373, 7323, 7373, 8373, 11373, 17323, 17373, 23373, 73323, 73373, 103323, 103373, 111373
OFFSET
1,2
LINKS
Robert P. P. McKone, Table of n, a(n) for n = 1..58
EXAMPLE
a(1) = onE, a(2) = thrEe, a(3) =thirtEen, a(4) = sEven, a(5) = Eight, a(6) = Eleven, etc.
MATHEMATICA
ePos[n_] := Flatten@Position[DeleteCases[Reverse@Characters@IntegerName[n, "Words"], a_ /; MemberQ[{" ", "\[Hyphen]"}, a]], "e"]; t = {}; i = 1; Monitor[Table[Do[If[MemberQ[ePos[i], n], Return[lst = AppendTo[t, i]; i = 1; lst], i++], \[Infinity]], {n, 1, 47, 1}] // Last, {ProgressIndicator[n, {1, 47}], n, i}] (* Robert P. P. McKone, Feb 07 2022 *)
CROSSREFS
Cf. A164790 ("e" in n-th position).
Cf. A173204 (similar for "n"), A173206 (similar for "t").
Sequence in context: A326609 A376022 A230362 * A140445 A320039 A242173
KEYWORD
nonn,word
AUTHOR
Claudio Meller, Feb 12 2010
EXTENSIONS
More terms from Robert P. P. McKone, Feb 08 2022
STATUS
approved