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A246351 Numbers k such that A048673(k) < k.

%I A246351 #12 Aug 18 2025 18:26:40
%S A246351 5,7,11,13,17,19,22,23,29,31,34,37,38,41,43,46,47,51,53,55,58,59,61,
%T A246351 62,65,67,71,73,74,77,79,82,83,85,86,87,89,94,95,97,101,103,106,107,
%U A246351 109,111,113,115,118,119,121,122,123,127,129,131,133,134,137,139,141,142,143,145,146,149,151,155,157,158,159
%N A246351 Numbers k such that A048673(k) < k.
%C A246351 The growth rate of the sequence seems to converge:
%C A246351        a(100) = 217
%C A246351       a(1000) = 2231
%C A246351      a(10000) = 21535
%C A246351     a(100000) = 214647
%C A246351    a(1000000) = 2155903
%C A246351   a(10000000) = 21553153
%C A246351 Please see comments in A246282.
%H A246351 Antti Karttunen, <a href="/A246351/b246351.txt">Table of n, a(n) for n = 1..10000</a>
%o A246351 (PARI)
%o A246351 default(primelimit, 2^22);
%o A246351 A003961(n) = my(f = factor(n)); for (i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); \\ From _Michel Marcus_
%o A246351 A048673(n) = (A003961(n)+1)/2;
%o A246351 isA246351(n) = (A048673(n) < n);
%o A246351 n = 0; i = 0; while(i < 10000, n++; if(isA246351(n), i++; write("b246351.txt", i, " ", n)));
%o A246351 (Scheme)
%o A246351 ;; With _Antti Karttunen_'s IntSeq-library.
%o A246351 (define A246351 (MATCHING-POS 1 1 (lambda (n) (< (A048673 n) n))))
%Y A246351 Complement: A246352.
%Y A246351 Setwise difference of A246281 and A048674.
%Y A246351 Cf. A048673, A246371, A246282.
%K A246351 nonn
%O A246351 1,1
%A A246351 _Antti Karttunen_, Aug 24 2014