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 A275845 #10 Aug 13 2016 11:08:55 %S A275845 0,1,4,2,6,3,12,8,16,5,15,10,18,21,22,7,20,13,24,27,28,9,26,17,48,30, %T A275845 52,33,34,11,60,32,64,23,56,36,66,61,70,39,40,14,73,38,78,29,67,42,72, %U A275845 80,76,74,85,45,84,46,88,19,89,44,90,97,94,35,81,49,87,99,93,91,105,53,96,104,100,54,109,25,108,110,112,51,111,121,114,117,118,41 %N A275845 Permutation of natural numbers: a(0) = 0, a(A153880(n)) = A255411(n), a(A273670(n)) = A256450(a(n)). %H A275845 Antti Karttunen, <a href="/A275845/b275845.txt">Table of n, a(n) for n = 0..5039</a> %H A275845 <a href="/index/Fa#facbase">Index entries for sequences related to factorial base representation</a> %H A275845 <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a> %F A275845 a(0) = 0; for n >= 1: if A257680(A225901(n)) = 0 [when n is one of the terms of A153880] then a(n) = A255411(A266193(n)), otherwise [when n is one of the terms of A273670], a(n) = A256450(a(A273663(n))). %F A275845 Other identities: %F A275845 a(A000142(n)) = A052849(n) for all n >= 2. %o A275845 (Scheme, with memoization-macro definec) %o A275845 (definec (A275845 n) (cond ((zero? n) n) ((zero? (A257680 (A225901 n))) (A255411 (A266193 n))) (else (A256450 (A275845 (A273663 n)))))) %Y A275845 Inverse: A275846. %Y A275845 Cf. A000142, A052849, A153880, A225901, A255411, A256450, A257680, A266193, A273663, A273670. %Y A275845 Similar permutations: A273667 (a more recursed variant), A275847, A275848. %K A275845 nonn,base %O A275845 0,3 %A A275845 _Antti Karttunen_, Aug 13 2016