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A343137 Positions of records in A188172. 0

%I

%S 1,7,63,315,945,1575,3465,10395,17325,26775,45045,135135,225225,

%T 405405,675675,1576575,2027025,2297295,3828825,6891885,11486475,

%U 26801775,34459425,43648605,72747675,130945815,218243025,509233725,654729075,1003917915,1527701175,3011753745,4583103525

%N Positions of records in A188172.

%e 945 is in the sequence as A188172(945) = 4 via the divisors 7, 15, 63 and 135 and no positive integer < 945 has at least four such (7 (mod 8)) divisors.

%t Function[{s, r}, Map[FirstPosition[s, #][[1]] &, r]] @@ {#, Union@ FoldList[Max, #]} &@ Array[DivisorSum[#, 1 &, Mod[#, 8] == 7 &] &, 10^6] (* _Michael De Vlieger_, Apr 08 2021 *)

%Y Cf. A188172, A188226.

%K nonn

%O 1,2

%A _David A. Corneth_, Apr 06 2021

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Last modified June 18 07:25 EDT 2021. Contains 345098 sequences. (Running on oeis4.)