%I #21 Apr 22 2023 10:28:52
%S 4,4,4,4,4,4,4,4,4,4,4,4,12,4,4,4,4,12,12,4,12,4,12,12,4,12,12,12,4,4,
%T 12,4,12,12,4,12,12,12,4,4,4,4,12,4,12,4,4,4,12,4,4,12,12,12,4,4,4,12,
%U 12,12,4,12,4,12,12,12,12,12,4,4,4,4,4
%N Group identifier of iterated Scrabble function.
%C Take the sequence A113172. Map it onto itself repeatedly. You will either end up at the fixed point, 12, or a loop of 4->7->8->9->4 (here represented by 4).
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Scrabble">Scrabble</a>
%e For example 10, spelled TEN is worth 3 points, THREE is worth 8 points and 8 is in the 4/7/8/9 loop, so a(10)=4
%o (Python)
%o from num2words import num2words
%o def A290205(n):
%o f = lambda n:sum((1,3,3,2,1,4,2,4,1,8,5,1,3,1,1,3,10,1,1,1,1,4,4,8,4,10)[a] for d in num2words(n).replace(' and ','') if 0<=(a:=ord(d)-97)<=25)
%o while True:
%o n = f(n)
%o if n in {4,7,8,9,4}: return 4
%o if n == 12: return 12 # _Chai Wah Wu_, Apr 21 2023
%Y Cf. A113172.
%K nonn,word
%O 0,1
%A _Michael Turniansky_, Jul 24 2017