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.

A382288 Number of records in the n-th composition in standard order.

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%I A382288 #10 May 06 2025 00:34:46
%S A382288 0,1,1,1,1,1,2,1,1,1,1,1,2,2,2,1,1,1,1,1,2,1,1,1,2,2,2,2,2,2,2,1,1,1,
%T A382288 1,1,1,1,1,1,2,2,1,1,2,1,1,1,2,2,2,2,3,2,2,2,2,2,2,2,2,2,2,1,1,1,1,1,
%U A382288 1,1,1,1,2,1,1,1,1,1,1,1,2,2,2,2,2,1,1
%N A382288 Number of records in the n-th composition in standard order.
%C A382288 Here a record is a part of the composition that is greater than all parts before it, reading left to right. The first part of any nonempty composition is a record so a(n) >= 1 for n > 0. See A066099 for the standard order of integer compositions.
%C A382288 The first appearance of k occurs at n = A164894(k) for k > 0.
%F A382288 a(A164894(n)) = n for n > 0.
%e A382288 The 883rd composition is (1, 2, 1, 1, 3, 1, 1) with records 1, 2, and 3; so a(883) = 3.
%e A382288                           ^  ^        ^
%o A382288 (Python)
%o A382288 def comp(n):
%o A382288     return # see A357625
%o A382288 def A382288(n):
%o A382288     r,c = 0,0
%o A382288     for i in comp(n):
%o A382288         if i > r:
%o A382288             c += 1
%o A382288             r = i
%o A382288     return c
%Y A382288 Cf. A066099, A124762, A124767, A124768, A164894, A333381, A333382, A382312.
%K A382288 nonn,easy
%O A382288 0,7
%A A382288 _John Tyler Rascoe_, Mar 20 2025