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.

A050445 Each prime appears later in alphabetical order (in American English) than the one before.

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%I A050445 #12 Aug 17 2022 22:29:46
%S A050445 2,211,223,2003,2027,2203,2221,2000000000003,2000000000203,
%T A050445 2000000002001,2000000002003,2000000002223,
%U A050445 2000000000000000000000000000000000041,2000000000000000000000000000000000429,2000000000000000000000000000000000653
%N A050445 Each prime appears later in alphabetical order (in American English) than the one before.
%C A050445 From _Michael S. Branicky_, Aug 17 2022: (Start)
%C A050445 As in the companion sequence A050444, spaces, hypens and the word "and" are not included in the comparisons.
%C A050445 In extending the sequence to large numbers, the "American system" (Weisstein link), also known as the "short scale" (Wikipedia link), was used.
%C A050445 The highest term is a(38) = 2*10^63 + 2*10^36 + 2*10^12 + 2202 ("two vigintillion two undecillion two trillion two thousand two hundred ninety three"). See b-file and link to US English names of terms. (End)
%H A050445 Michael S. Branicky, <a href="/A050445/b050445.txt">Table of n, a(n) for n = 1..38</a>
%H A050445 Michael S. Branicky, <a href="/A050445/a050445.txt">US English names of terms</a>
%H A050445 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/LargeNumber.html">Large Number</a>
%H A050445 Wikipedia, <a href="https://en.wikipedia.org/wiki/Names_of_large_numbers">Names of Large Numbers</a>
%H A050445 Wiktionary, <a href="https://en.wiktionary.org/wiki/one_hundred_one">one hundred one</a> (US)
%H A050445 Wiktionary, <a href="https://en.wiktionary.org/wiki/one_hundred_and_one">one hundred and one</a> (UK)
%e A050445 Prime 2 ("two") is followed in alphabetic order first by prime 211 ("two hundred eleven").
%o A050445 (Python)
%o A050445 from sympy import isprime
%o A050445 from num2words import num2words
%o A050445 def n2w(n): return num2words(n).replace(" and", "").replace(chr(44), "").replace(chr(32), "").replace("-", "")
%o A050445 def afind(limit, start=2):
%o A050445     alst, last, t = [], start-1, start
%o A050445     while t <= limit:
%o A050445         target = n2w(last)
%o A050445         while not isprime(t) or n2w(t) <= target:
%o A050445             t += 1
%o A050445             if t > limit: return alst
%o A050445         last = t; alst.append(t)
%o A050445     return alst
%o A050445 print(afind(3000)) # _Michael S. Branicky_, Aug 17 2022
%Y A050445 Cf. A050444, A180301.
%K A050445 base,fini,full,nonn,word
%O A050445 1,1
%A A050445 Michael Lugo (mlugo(AT)thelabelguy.com), Dec 23 1999
%E A050445 If you accept "vigintillion" as a name for 10^63 then there are more terms.
%E A050445 Offset changed, a(4) inserted and a(8) and beyond from _Michael S. Branicky_, Aug 17 2022