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A097963
["comma"], is the first, fifteenth, twenty-sixth, fortieth, ... character in this sentence, including spaces and punctuations.
1
1, 15, 26, 40, 50, 60, 70, 82, 97, 113, 137, 165, 190, 213, 237, 265, 290, 313, 339, 367, 396, 424, 452, 479, 507, 529, 556, 582, 610, 629, 655, 680, 703, 724, 753, 780, 805, 826, 854, 882, 911, 934, 962, 989, 1016, 1040, 1063, 1089, 1116, 1152, 1191, 1230
OFFSET
1,2
COMMENTS
Yes, the definition begins with a comma!
LINKS
FORMULA
After a(2) = 15, the remaining terms are given by the recursion a(n+1) = a(n) + 2 + length(OrdinalName(a(n))); e.g., a(3) = a(2) + 2 + length(OrdinalName(a(2))) = 15 + 2 + length("fifteenth") = 15 + 2 + 9 = 26. - Jon E. Schoenfield, Aug 13 2007
EXAMPLE
Label the coordinates:
00000000011111111112222222222333333333344444444445...
12345678901234567890123456789012345678901234567890... Then (comma)
["Comma"], is the first, fifteenth, twenty-sixth, fortieth, fiftieth, fifty-ninth, seventy-second, eighty-eighth, one hundred third, one hundred twenty-second, ... character.
PROG
(Python)
from itertools import accumulate, repeat
from num2words import num2words
A097963_list = [1]+list(accumulate(repeat(15, 100), lambda x, _: x+2+len(num2words(x, to='ordinal').replace(' and ', ' ').replace(', ', ' ')))) # Chai Wah Wu, Aug 30 2021
CROSSREFS
KEYWORD
nonn,base,nice,easy,word
AUTHOR
Ray G. Opao, Sep 21 2004
EXTENSIONS
Corrected and extended by Jon E. Schoenfield, Aug 13 2007
STATUS
approved