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A246371 Numbers n such that, if 2n-1 = Product_{k >= 1} (p_k)^(c_k) then n > Product_{k >= 1} (p_{k-1})^(c_k), where p_k indicates the k-th prime, A000040(k).

%I A246371 #34 Aug 01 2022 15:02:01
%S A246371 5,8,11,13,14,17,18,23,28,32,38,39,41,43,50,53,58,59,61,63,68,73,74,
%T A246371 77,83,86,88,94,95,98,104,113,116,122,123,128,131,137,138,140,143,149,
%U A246371 158,163,167,172,173,176,179,182,185,188,193,194,200,203,212,213,215,218,221,228,230,233,238,239,242,248,254,257
%N A246371 Numbers n such that, if 2n-1 = Product_{k >= 1} (p_k)^(c_k) then n > Product_{k >= 1} (p_{k-1})^(c_k), where p_k indicates the k-th prime, A000040(k).
%C A246371 Numbers n such that A064216(n) < n.
%C A246371 Numbers n such that A064989(2n-1) < n.
%C A246371 Note: This sequence has remarkable but possibly merely coincidental overlap with A053726. On Dec 22 2014, _Matthijs Coster_ mistakenly attached a comment intended for that sequence to this one. On Apr 17 2015, _Antti Karttunen_ noted the error. I have moved the comment to the correct sequence, and have removed Karttunen's note. - _Allan C. Wechsler_, Aug 01 2022
%H A246371 Antti Karttunen, <a href="/A246371/b246371.txt">Table of n, a(n) for n = 1..10000</a>
%H A246371 Matthijs Coster, <a href="https://pyth.eu/uploads/user/ArchiefPDF/Pyth54-2.pdf">Oplossing Zomerprijsvraag</a>, Pythagoras 54/2 (2014) 4-7.
%o A246371 (PARI)
%o A246371 default(primelimit, 2^30);
%o A246371 A064989(n) = {my(f); f = factor(n); if((n>1 && f[1,1]==2), f[1,2] = 0); for (i=1, #f~, f[i,1] = precprime(f[i,1]-1)); factorback(f)};
%o A246371 A064216(n) = A064989((2*n)-1);
%o A246371 isA246371(n) = (A064216(n) < n);
%o A246371 n = 0; i = 0; while(i < 10000, n++; if(isA246371(n), i++; write("b246371.txt", i, " ", n)));
%o A246371 (Scheme, with _Antti Karttunen_'s IntSeq-library)
%o A246371 (define A246371 (MATCHING-POS 1 1 (lambda (n) (< (A064216 n) n))))
%Y A246371 Complement: A246372.
%Y A246371 Setwise difference of A246361 and A048674.
%Y A246371 Subsequence of A104275 and A053726 (20 is the first term > 1 which is not in this sequence).
%Y A246371 Subsequence: A246374 (the primes present in this sequence).
%Y A246371 Cf. A000040, A064216, A064989, A246351.
%K A246371 nonn
%O A246371 1,1
%A A246371 _Antti Karttunen_, Aug 24 2014