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A085468 Odd numbers m such that there is at least one k dividing (m-1)!-1 (m <= k <= 2*m). 2

%I #18 Apr 23 2020 03:30:11

%S 1,43,45,47,49,53,97,99,121,123,169,237,273,319,329,343,367,369,375,

%T 499,533,573,581,611,617,653,661,703,719,737,747,757,787,807,833,845,

%U 879,925,931,971,981,995,1071,1093,1109,1125,1163,1185,1197,1227,1249,1283,1305

%N Odd numbers m such that there is at least one k dividing (m-1)!-1 (m <= k <= 2*m).

%H Amiram Eldar, <a href="/A085468/b085468.txt">Table of n, a(n) for n = 1..1000</a>

%t seqQ[n_] := AnyTrue[Range[n, 2n], Divisible[(n - 1)! - 1, #] &]; Select[2 * Range[700] - 1, seqQ] (* _Amiram Eldar_, Apr 23 2020 *)

%o (PARI) for(n=1,650,if(sum(k=n,2*n,if(((n-1)!-1)%k,0,1))>0,if(n%2==1,print1(n,","))))

%Y Odd terms of A085477.

%K nonn

%O 1,2

%A _Benoit Cloitre_, Aug 14 2003

%E More terms from _Jinyuan Wang_, Apr 03 2020

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Last modified April 24 09:42 EDT 2024. Contains 371935 sequences. (Running on oeis4.)