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%I #9 Dec 02 2018 20:53:43
%S 1,1,2,2,3,1,4,1,3,1,5,1,6,2,1,2,7,1,8,1,1,4,9,1,10,2,5,2,11,1,12,1,1,
%T 3,2,1,13,3,3,1,14,1,15,1,2,6,16,1,7,1,3,3,17,2,2,1,2,8,18,1,19,9,1,4,
%U 1,1,20,3,4,2,21,1,22,2,2,2,3,1,23,1,24,3,25,1,1,4,5,3,26,1,1,5,3,10,5,1,27,3,2,1,28,1,29,1,1
%N Ordinal transform of A322023.
%C Positions where 1, 2, 3, 4, 5, ... occur for the first time are 1, 3, 5, 7, 11, 13, 17, 19, 23, 25, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 81, 83, 89, 97, 101, 103, 107, 109, 113, 121, 127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 187, 191, 193, ... Note that this is not a subsequence of A000961; for example, 187 = 11*17 is a semiprime.
%H Antti Karttunen, <a href="/A322025/b322025.txt">Table of n, a(n) for n = 1..65537</a>
%o (PARI)
%o \\ Needs also code from A322023.
%o ordinal_transform(invec) = { my(om = Map(), outvec = vector(length(invec)), pt); for(i=1, length(invec), if(mapisdefined(om,invec[i]), pt = mapget(om, invec[i]), pt = 0); outvec[i] = (1+pt); mapput(om,invec[i],(1+pt))); outvec; };
%o v322025 = ordinal_transform(v322023);
%o A322025(n) = v322025[n];
%Y Cf. A000010, A002322, A081373, A303753, A303755, A303756, A303777, A322023.
%K nonn
%O 1,3
%A _Antti Karttunen_, Dec 01 2018
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