A066773 -id:A066773 - cp's OEIS frontend

A066905 Squares in A006577.

0, 1, 16, 9, 9, 4, 16, 16, 16, 9, 9, 9, 25, 25, 25, 25, 25, 100, 121, 36, 36, 36, 36, 49, 16, 16, 16, 16, 16, 16, 16, 16, 81, 81, 9, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 100, 100, 100, 25, 144, 25, 100, 25, 25, 144, 144, 25, 25, 144, 64, 64, 64, 64, 64, 25, 25, 64, 64

Offset: 1

K. B. Subramaniam (kb_subramaniambalu(AT)yahoo.com), Dec 20 2001

nonn

Cf. A006577, A066773.

steps[ n_ ] := For[ nn=n; ct=0, True, ct++, If[ nn==1, Return[ ct ] ]; nn=If[ EvenQ[ nn ], nn/2, 3nn+1 ] ]; Select[ steps/@Range[ 1, 1000 ], IntegerQ[ Sqrt[ # ] ]& ]

More terms from Dean Hickerson, Jan 19 2002

Offset 1 from Michel Marcus, Jul 25 2021

A066756 Smallest number that requires n^3 steps to reach 1 in its Collatz trajectory (counting x/2 and 3x+1 steps).

Original entry on oeis.org

1, 2, 6, 65, 673, 342, 2919, 129991, 1590511, 301695657, 1412987847

Offset: 0

Randall L Rathbun, Jan 18 2002

a(11) > 7*10^11. - Donovan Johnson

			a(2) = 6 since the trajectory of 6 requires 2^3 = 8 steps to reach 1 (the trajectory is 6 -> 3 -> 10 -> 5 -> 16 -> 8 -> 4 -> 2 -> 1), and 6 is the smallest number for which this is the case.

R. K. Guy, Problem E16, Unsolved Problems in Number Theory, 2nd edition, Springer-Verlag, NY pp. 215-218

Index entries for sequences related to 3x+1 (or Collatz) problem

Cf. A006577, A066773.

Mapping at each step for Collatz problem: x -> x/2 if n is even, else x -> 3*x+1; count the steps until x=1.

More terms from Larry Reeves (larryr(AT)acm.org), Apr 12 2002
a(10) from Donovan Johnson, Nov 13 2010
Edited by Jon E. Schoenfield, Jan 28 2014

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A066905 Squares in A006577.

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A066756 Smallest number that requires n^3 steps to reach 1 in its Collatz trajectory (counting x/2 and 3x+1 steps).

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