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.

Showing 1-3 of 3 results.

A226634 Length of the primitive 3x-k cycle associated with A226633(n).

Original entry on oeis.org

1, 4, 6, 17, 19, 34, 12, 9, 5, 22, 12, 17, 17, 69, 7, 18, 44, 38, 22, 48, 6, 68, 44, 30, 54, 38, 68, 14, 22, 44, 23, 30, 84, 8, 17, 17, 30, 12, 68, 18, 7, 66, 30, 22, 85, 10, 14, 66, 44, 30, 14, 54, 44, 12, 68, 44, 9, 38, 34, 14, 55, 8, 56, 50, 36, 44, 25, 37
Offset: 1

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Author

Geoffrey H. Morley, Jun 14 2013

Keywords

Crossrefs

Cf. A102284.

A226630 Positive integers k with at least one primitive cycle of positive integers under iteration by the 3x-k function.

Original entry on oeis.org

1, 11, 17, 19, 23, 25, 29, 31, 49, 77, 85, 95, 97, 113, 115, 119, 121, 131, 139, 145, 179, 181, 185, 193, 217, 311, 313, 371, 385, 407, 431, 451, 467, 473, 475, 485, 491, 493, 503, 527, 601, 605, 641, 695, 697, 791, 805, 847, 973, 1163, 1219, 1241, 1295, 1417
Offset: 1

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Author

Geoffrey H. Morley, Jun 13 2013

Keywords

Comments

A cycle is called primitive if its elements are not a common multiple of the elements of another cycle.
The 3x-k function T_k is defined by T_k(x) = x/2 if x is even, (3x-k)/2 if x is odd. GCD(k,6)=1.

Crossrefs

Cf. A226633.

A102280 Let k = n-th number == 1 or 5 mod 6 (A007310(n)); consider the generalized 3x+1 map T_k defined by T_k(n) = (3n+k)/2 if n odd, n/2 if n even; then a(n) = smallest positive number m which is in a primitive cycle of T_k.

Original entry on oeis.org

1, 1, 5, 1, 1, 1, 5, 5, 7, 1, 13, 13, 19, 1, 1, 5, 25, 103, 1, 1, 1, 19, 17, 29, 5, 1, 1, 65, 7, 17, 1, 1, 1, 7, 5, 1, 19, 1, 13, 1, 5, 1, 1, 13, 11, 1, 11, 7, 1, 19, 41, 1, 13, 11, 11, 13, 11, 7, 29, 5, 11, 1, 5, 47, 1, 5, 13, 1, 43, 1, 37, 1, 17, 5, 35, 5, 7, 5, 11, 1, 7, 43, 1, 91, 1, 1, 29, 7, 47, 55, 17, 1, 13
Offset: 1

Views

Author

N. J. A. Sloane, Feb 19 2005

Keywords

Crossrefs

Extensions

a(12)[k=35] and a(25)[k=73] corrected and more terms added by Geoffrey H. Morley, Mar 14 2013
Showing 1-3 of 3 results.