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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.

A249436 Integers n such that n/2 < A249151(n) < n.

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%I A249436 #13 Sep 04 2025 11:26:56
%S A249436 11,29,44,55,59,69,71,111,119,125,139,188,215,223,230,233,239,251,324,
%T A249436 335,349,351,447,458,474,479,493,494,503,509,560,593,599,647,662,701,
%U A249436 714,719,831,835,849,895,956,959,979,991,1000,1007,1019,1034,1063,1077,1169,1224,1319,1322,1364,1376,1424,1427,1448,1507
%N A249436 Integers n such that n/2 < A249151(n) < n.
%C A249436 Integers n such that A001142(n) [product of elements on row n of Pascal's triangle] is divisible by floor[(n+1)/2]! but not by n!
%C A249436 These are the abscissas of "stray points" in the sparsely populated region between the two topmost rays visible in the scatter plot of A249151 which have slopes 1 and 1/2: A249434 (A006093) and A249424.
%H A249436 Chai Wah Wu, <a href="/A249436/b249436.txt">Table of n, a(n) for n = 1..200</a> (terms 1..115 from Antti Karttunen)
%o A249436 (Scheme, with _Antti Karttunen_'s IntSeq-library, two alternative definitions)
%o A249436 (define A249436 (MATCHING-POS 1 0 (lambda (n) (and (> (A249151 n) (/ n 2)) (< (A249151 n) n)))))
%o A249436 (define A249436 (MATCHING-POS 1 0 (lambda (n) (and (zero? (modulo (A001142 n) (A000142 (floor->exact (/ (+ n 1) 2))))) (not (zero? (modulo (A001142 n) (A000142 n))))))))
%Y A249436 A249437 gives the corresponding values at those points.
%Y A249436 Subsequence of A249433.
%Y A249436 Cf. A000142, A001142, A249151, A006093, A249424, A249434.
%K A249436 nonn,changed
%O A249436 1,1
%A A249436 _Antti Karttunen_, Nov 02 2014