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.
%I A380248 #17 Aug 08 2025 20:14:21 %S A380248 3,8,7,1,12,6,4,2,11,13,10,9,5 %N A380248 The order of the 13 cards of one suit such that after the SpellUnder-Down deal the cards are in order; a(n) is the n-th card in the deck. %C A380248 Number 1 corresponds to ace, 11 to jack, 12 to queen, 13 to king. %C A380248 In the SpellUnder-Down deal, we spell the next card, putting a card under for each letter in the name, then we deal the next card. So we start with putting 3 cards under for A-C-E, then deal, then 3 cards under for T-W-O, then deal, then 5 cards under for T-H-R-E-E, then deal. The dealing sequence is highly irregular because it depends on English spelling. The dealing pattern starts: UUUDUUUDUUUUUD. %C A380248 The sequence is a permutation of 13 numbers. %e A380248 The first card dealt is the fourth card in the deck, thus, the fourth card must be an ace. %Y A380248 Cf. A005589, A006257, A225381, A321298, A378635, A380201, A380202, A380204, A380246, A380247. %K A380248 nonn,fini,full,word %O A380248 1,1 %A A380248 _Tanya Khovanova_ and the MIT PRIMES STEP junior group, Jan 17 2025