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.

A322182 a(1) = 1, and for any n > 0, a(n+1) is the number of occurrences of the n-th digit of the sequence among the first n digits of the sequence.

This page as a plain text file.
%I A322182 #11 Dec 05 2018 03:02:22
%S A322182 1,1,2,1,3,1,4,1,5,1,6,1,7,1,8,1,9,1,10,11,1,12,13,14,15,2,16,2,17,2,
%T A322182 18,2,3,19,2,4,20,2,5,21,2,6,3,22,2,7,3,8,2,9,3,10,23,11,3,4,12,13,14,
%U A322182 3,5,3,15,3,6,24,3,16,7,25,26,8,4,27,17,28,9,29
%N A322182 a(1) = 1, and for any n > 0, a(n+1) is the number of occurrences of the n-th digit of the sequence among the first n digits of the sequence.
%C A322182 In other words, if we take the ordinal transform of the digits of the sequence and prepend the number 1, then we obtain the sequence again.
%C A322182 The number 1 appears 11 times.
%C A322182 Any number > 1 appears 10 times.
%C A322182 The sequence contains arbitrarily large runs of consecutive numbers.
%H A322182 Rémy Sigrist, <a href="/A322182/b322182.txt">Table of n, a(n) for n = 1..10000</a>
%H A322182 Rémy Sigrist, <a href="/A322182/a322182.png">Colored scatterplot of (n, a(n)) for n = 1..1000000</a> (where the color is function of the n-th digit of the sequence)
%e A322182 The first terms of the sequence, alongside the (n-1)-th digit of the sequence, are:
%e A322182   n    a(n)  (n-1)-th digit
%e A322182   ---  ----  --------------
%e A322182     1     1             N/A
%e A322182     2     1               1
%e A322182     3     2               1
%e A322182     4     1               2
%e A322182     5     3               1
%e A322182     6     1               3
%e A322182     7     4               1
%e A322182     8     1               4
%e A322182     9     5               1
%e A322182    10     1               5
%e A322182    11     6               1
%e A322182    12     1               6
%e A322182    13     7               1
%e A322182    14     1               7
%e A322182    15     8               1
%e A322182    16     1               8
%e A322182    17     9               1
%e A322182    18     1               9
%e A322182    19    10               1
%e A322182    20    11               1
%e A322182    21     1               0
%o A322182 (PARI) a = [1]; ord = vector(base = 10); for (k=1, 59, a = concat(a, apply(d -> ord[1+d]++, digits(a[k], #ord)))); print (a)
%Y A322182 Cf. A248034.
%K A322182 nonn,base
%O A322182 1,3
%A A322182 _Rémy Sigrist_, Nov 30 2018