A291173 Totient superdeficient numbers: numbers n > 1 such that s(n)/n < s(m)/m for all m < n, where s(n) is the sum of iterated phi(n) (A092693).

2, 42, 90, 210, 630, 1050, 1470, 2310, 6930, 16170, 30030, 90090, 150150, 210210, 570570, 690690, 870870, 2072070, 3573570, 3993990, 4834830

Offset: 1

Author

Amiram Eldar, Aug 19 2017

Keywords

• nonn
• more

Comments

A variation of A286268 (Totient superabundant numbers).

Examples

			The values of A092693(n)/n for n = 2, 42, 90 are 0.5, 0.452..., 0.433..., which are records of lowest values.
		

Crossrefs

Cf. A092693, A286268, A291174.

Programs

Mathematica

Function[s, Flatten[First@Position[s, #] & /@ Union@Rest@FoldList[Max, 0, s]]]@ Table[n/(Total@FixedPointList[EulerPhi, n] - (n + 1)), {n, 2, 10^5}]+1 (* after Michael De Vlieger at A286268 and Alonso del Arte at A092693 *)