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.

A022516 Describe previous term from the right (method B - initial term is 5).

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%I A022516 #12 Oct 06 2019 16:55:06
%S A022516 5,51,1151,115112,21125112,211251211221,112212211151211221,
%T A022516 1122122111511322112212,21112212223112511322112212,
%U A022516 21112212223112512112312311221321
%N A022516 Describe previous term from the right (method B - initial term is 5).
%C A022516 Method B = 'digit'-indication followed by 'frequency'.
%H A022516 Reinhard Zumkeller, <a href="/A022516/b022516.txt">Table of n, a(n) for n = 0..21</a>
%e A022516 The term after 1151 is obtained by saying "1 once, 5 once, 1 twice", which gives 115112.
%o A022516 (Haskell)
%o A022516 import Data.List (group, transpose)
%o A022516 a022516 n = a022516_list !! n
%o A022516 a022516_list = 5 : f [5] :: [Integer] where
%o A022516    f xs = (read $ concatMap show ys) : f ys where
%o A022516           ys = concat $ transpose [map head zss, map length zss]
%o A022516           zss = reverse $ group xs
%o A022516 -- _Reinhard Zumkeller_, Jan 26 2014
%Y A022516 Cf. A022481, A022488, A022514-A022520.
%K A022516 nonn,base,easy,nice
%O A022516 0,1
%A A022516 _N. J. A. Sloane_
%E A022516 More terms from _Patrick De Geest_, Jun 15 1999