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A246349 Positions of records in A246272.

%I A246349 #9 Sep 01 2014 11:46:31
%S A246349 1,2,6,10,30,42,210,330,462,2310,6090,30030,66990,94710,434910,651630,
%T A246349 1292646,1610070,2478630,2497110,2916690,13220130,20930910,52582530,
%U A246349 60690630
%N A246349 Positions of records in A246272.
%C A246349 All terms are squarefree. (See the comments in A246272).
%C A246349 From 2 onward they factorize as: 2, 2*3, 2*5, 2*3*5, 2*3*7, 2*3*5*7, 2*3*5*11, 2*3*7*11, 2*3*5*7*11, 2*3*5*7*29, 2*3*5*7*11*13, 2*3*5*7*11*29, 2*3*5*7*11*41, 2*3*5*7*19*109, 2*3*5*7*29*107, 2*3*17*19*23*29, 2*3*5*7*11*17*41, 2*3*5*7*11*29*37, 2*3*5*7*11*23*47, 2*3*5*7*17*19*43, 2*3*5*7*11*59*97, 2*3*5*7*11*13*17*41, 2*3*5*7*11*13*17*103, 2*3*5*7*11*13*43*47, ...
%o A246349 (PARI)
%o A246349 default(primelimit, 2^22)
%o A246349 A003961(n) = my(f = factor(n)); for (i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); \\ Using code of _Michel Marcus_
%o A246349 A065338(n) = my(f = factor(n)); for (i=1, #f~, f[i, 1] = (f[i, 1]%4)); factorback(f);
%o A246349 A246272(n) = {my(i); i=0; while((A065338(n)!=1), i++; n = A003961(n)); i};
%o A246349 \\ Compute the b-files for both the positions of records (A246349) and their values (A246350) at the same time:
%o A246349 prevmax = -1; i = 0; for(n=1, 60690630, if((k=A246272(n)) > prevmax, prevmax = k; i++; write("b246349.txt", i, " ", n); write("b246350.txt", i, " ", k)));
%o A246349 (Scheme, with _Antti Karttunen_'s IntSeq-library)
%o A246349 (define A246349 (RECORD-POS 1 1 A246272))
%Y A246349 A246350 gives the corresponding record values.
%Y A246349 Cf. A246272.
%K A246349 nonn
%O A246349 1,2
%A A246349 _Antti Karttunen_, Aug 23 2014