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 A377915 #15 Nov 30 2024 06:23:48 %S A377915 1,2,3,4,5,6,7,8,9,10,11,12,13,28,14,15,43,16,17,56,18,19,67,20,21,22, %T A377915 44,23,24,57,25,26,68,27,29,30,31,32,45,33,34,58,35,36,69,37,38,39,59, %U A377915 40,41,70,42,46,47,48,49,60,50,51,71,52,53,54,72,55,61,62,63,64,73,65,66,74,75,76,77,78,201,79,80,310,81,82,406,83,84,491,85,86,87,88,202,203 %N A377915 a(n) = m means A342042(n) is the m-th term of A377912. %C A377915 That is, a(n) = m means A342042(n) = A377912(m). %C A377915 The reason for looking at this is that A342042 is a permutation of A377912. But not all nonnegative integers appear in either sequence. The present sequence shows the numbers in A342042 in the order in which they appear in A377912. It is a permutation of the natural numbers. A377916 gives the inverse permutation. %H A377915 Rémy Sigrist, <a href="/A377915/b377915.txt">Table of n, a(n) for n = 1..20000</a> %H A377915 Rémy Sigrist, <a href="/A377915/a377915.gp.txt">PARI program</a> %H A377915 <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a> %e A377915 A342042(14) = 30 is the 28-th term of A377912, so a(14) = 38. %o A377915 (PARI) \\ See Links section. %Y A377915 Cf. A342042, A377912, A377916. %K A377915 nonn,base %O A377915 1,2 %A A377915 _N. J. A. Sloane_, Nov 29 2024