A108017 Position of integer n in the list of first n natural numbers written out in English (without "and") and arranged in alphabetical order.
1, 2, 2, 1, 1, 4, 4, 1, 4, 8, 2, 11, 10, 5, 3, 11, 10, 2, 9, 19, 21, 22, 22, 21, 21, 24, 24, 21, 24, 16, 17, 18, 18, 17, 20, 20, 17, 20, 5, 6, 7, 7, 6, 6, 9, 9, 6, 9, 4, 5, 6, 6, 5, 5, 8, 8, 5, 8, 33, 34, 35, 35, 34, 34, 37, 37, 34, 37, 32, 33, 34, 34, 33, 33, 36, 36, 33, 36, 2, 3, 4, 4, 3
Offset: 1
Examples
We have a(19)=9 because of the ordered list: EIGHT, EIGHTEEN, ELEVEN, FIFTEEN, FIVE, FOUR, FOURTEEN, NINE, NINETEEN, ..., TWELVE, TWO.
Crossrefs
Cf. A214095 (in French).
Programs
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PARI
lista() = {my(v = ["one", "two", "three", "four", "five", "six", "seven", "eight", "nine", "ten", "eleven", "twelve", "thirteen", "fourteen", "fifteen", "sixteen", "seventeen", "eighteen", "nineteen", "twenty"], vs); for (i=1, #v, vp = vector(i, k, v[k]); vs = vecsort(vp); for (k=1, #vp, if (vs[k] == v[i], print1(k, ", "); break);););} \\ Michel Marcus, Jan 03 2019