cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A322316 Lexicographically earliest such sequence a that a(i) = a(j) => A122841(i) = A122841(j) and A244417(i) = A244417(j), for all i, j.

Original entry on oeis.org

1, 2, 2, 3, 1, 4, 1, 5, 3, 2, 1, 6, 1, 2, 2, 7, 1, 6, 1, 3, 2, 2, 1, 8, 1, 2, 5, 3, 1, 4, 1, 9, 2, 2, 1, 10, 1, 2, 2, 5, 1, 4, 1, 3, 3, 2, 1, 11, 1, 2, 2, 3, 1, 8, 1, 5, 2, 2, 1, 6, 1, 2, 3, 12, 1, 4, 1, 3, 2, 2, 1, 13, 1, 2, 2, 3, 1, 4, 1, 7, 7, 2, 1, 6, 1, 2, 2, 5, 1, 6, 1, 3, 2, 2, 1, 14, 1, 2, 3, 3, 1, 4, 1, 5, 2
Offset: 1

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Author

Antti Karttunen, Dec 04 2018

Keywords

Comments

Restricted growth sequence transform of the ordered pair [A122841(n), A244417(n)].
Essentially also the restricted growth sequence transform of the unordered pair {A007814(n), A007949(n)}.
For all i, j: a(i) = a(j) => A072078(i) = A072078(j).

Crossrefs

Cf. A007814, A007949, A122841, A244417, A322026, A322317 (ordinal transform).

Programs

  • PARI
    up_to = 65537;
    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; };
    A007814(n) = valuation(n,2);
    A007949(n) = valuation(n,3);
    A122841(n) = min(A007814(n), A007949(n));
    A244417(n) = max(valuation(n,2), valuation(n,3));
    v322316 = rgs_transform(vector(up_to, n, [A122841(n), A244417(n)]));
    \\ The following is equivalent:
    \\ v322316 = rgs_transform(vector(up_to, n, Set([A007814(n), A007949(n)])));
    A322316(n) = v322316[n];