A377915 - OEIS

%I #15 Nov 30 2024 06:23:48

%S 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 44,23,24,57,25,26,68,27,29,30,31,32,45,33,34,58,35,36,69,37,38,39,59,

%U 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 a(n) = m means A342042(n) is the m-th term of A377912.

%C That is, a(n) = m means A342042(n) = A377912(m).

%C 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 Rémy Sigrist, <a href="/A377915/b377915.txt">Table of n, a(n) for n = 1..20000</a>

%H Rémy Sigrist, <a href="/A377915/a377915.gp.txt">PARI program</a>

%H <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a>

%e A342042(14) = 30 is the 28-th term of A377912, so a(14) = 38.

%o (PARI) \\ See Links section.

%Y Cf. A342042, A377912, A377916.

%K nonn,base,new

%O 1,2

%A _N. J. A. Sloane_, Nov 29 2024