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A265899 After a(1) = 1, positions of descents in A265894.

%I A265899 #18 Jan 14 2025 01:53:29
%S A265899 1,3,6,8,11,14,17,20,24,27,31,34,38,41,45,49,53,57,61,65,69,73,77,81,
%T A265899 85,89,94,98,102,106,111,115,120,124,128,133,137,142,146,151,156,160,
%U A265899 165,169,174,179,184,188,193,198,202,207,212,217,222,227,231,236,241,246,251,256,261,266,271,276,281,286,291,296,301
%N A265899 After a(1) = 1, positions of descents in A265894.
%C A265899 Numbers n for which A099563(A001813(n)) <= A099563(A001813(n-1)), where A001813(n) = (2n)! / n!, and A099563 gives the most significant digit in the factorial base representation (A007623) of n.
%H A265899 Antti Karttunen, <a href="/A265899/b265899.txt">Table of n, a(n) for n = 1..1503</a>
%o A265899 (PARI)
%o A265899 A099563(n) = { my(i=2,dig=0); until(0==n, dig = n % i; n = (n - dig)/i; i++); return(dig); };
%o A265899 A265894 = n -> A099563((2*n)! / n!);
%o A265899 my(i=0, p=1, n=0); while(i < 60, n++; my(k = A265894(n)); if(k <= p, i++; print1(n, ", ")); p = k; );
%o A265899 (Scheme)
%o A265899 ;; With _Antti Karttunen_'s IntSeq-library.
%o A265899 (define A265899 (MATCHING-POS 1 1 (lambda (n) (<= (A265894 n) (A265894 (- n 1))))))
%Y A265899 Cf. A001813, A007623, A099563, A265894.
%Y A265899 Cf. A265898 (a subsequence), A266119 (first differences), A266120 (terms immediately before descents).
%Y A265899 Cf. also A031435.
%K A265899 nonn
%O A265899 1,2
%A A265899 _Antti Karttunen_, Dec 24 2015