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A322026 Lexicographically earliest such sequence a that a(i) = a(j) => A007814(i) = A007814(j) and A007949(i) = A007949(j), for all i, j, where A007814 and A007949 give the 2-adic and 3-adic valuation of n. 11

%I #31 Dec 20 2018 23:18:52

%S 1,2,3,4,1,5,1,6,7,2,1,8,1,2,3,9,1,10,1,4,3,2,1,11,1,2,12,4,1,5,1,13,

%T 3,2,1,14,1,2,3,6,1,5,1,4,7,2,1,15,1,2,3,4,1,16,1,6,3,2,1,8,1,2,7,17,

%U 1,5,1,4,3,2,1,18,1,2,3,4,1,5,1,9,19,2,1,8,1,2,3,6,1,10,1,4,3,2,1,20,1,2,7,4,1,5,1,6,3

%N Lexicographically earliest such sequence a that a(i) = a(j) => A007814(i) = A007814(j) and A007949(i) = A007949(j), for all i, j, where A007814 and A007949 give the 2-adic and 3-adic valuation of n.

%C Restricted growth sequence transform of the ordered pair [A007814(n), A007949(n)].

%C For all i, j:

%C A305900(i) = A305900(j) => a(i) = a(j),

%C a(i) = a(j) => A122841(i) = A122841(j),

%C a(i) = a(j) => A244417(i) = A244417(j),

%C a(i) = a(j) => A322316(i) = A322316(j) => A072078(i) = A072078(j).

%C If and only if a(k) > a(i) for all k > i then k is in A003586, - _David A. Corneth_, Dec 03 2018

%C That is, A003586 gives the positions of records (1, 2, 3, 4, 5, ...) in this sequence.

%C Sequence A126760 (without its initial zero) and this sequence are ordinal transforms of each other.

%H Antti Karttunen, <a href="/A322026/b322026.txt">Table of n, a(n) for n = 1..65537</a>

%F For s = A003586(n), a(s) = n = a((6k+1)*s) = a((6k-1)*s), where s is the n-th 3-smooth number and k > 0. - _David A. Corneth_, Dec 03 2018

%F A065331(n) = A003586(a(n)). - _David A. Corneth_, Dec 04 2018

%o (PARI)

%o up_to = 65537;

%o rgs_transform(invec) = { my(om = Map(), outvec = vector(length(invec)), u=1); for(i=1, length(invec), if(mapisdefined(om,invec[i]), my(pp = mapget(om, invec[i])); outvec[i] = outvec[pp] , mapput(om,invec[i],i); outvec[i] = u; u++ )); outvec; };

%o A007814(n) = valuation(n,2);

%o A007949(n) = valuation(n,3);

%o v322026 = rgs_transform(vector(up_to, n, [A007814(n), A007949(n)]));

%o A322026(n) = v322026[n];

%Y Cf. A003586 (positions of records, the first occurrence of n), A007814, A007949, A065331, A072078, A087465, A122841, A126760 (ordinal transform), A322316.

%Y Cf. also A247714 and A255975.

%K nonn

%O 1,2

%A _Antti Karttunen_, Dec 03 2018

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Last modified August 27 01:48 EDT 2024. Contains 375462 sequences. (Running on oeis4.)