A078151 - OEIS

A078151

Smallest x such that d[phi(x)]-phi[d(x)]=-n, where d()=A000005(),phi()=A000010(); restricted to cases when d[phi(x)]-phi[d(x)] is negative.

240, 120, 960, 6528, 4080, 1920, 15360, 24960, 61440, 13440, 16320, 87360, 983040, 196560, 1432080, 130560, 861840, 32640, 98280, 114240, 2545920, 293760, 261120, 967680, 174720, 2673216, 4194240, 1081080, 1044480, 913920, 1659840, 424320

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

LINKS

Table of n, a(n) for n=1..32.

EXAMPLE

a(77)=2970240, since d[phi(2970240)]-phi[d(2970240)]=-77 first appears here; while d[phi(x)]-phi[d(x)] takes large positive values,absolute value of negative differences grows significantly slower.

CROSSREFS

Cf. A000005, A000010.

Sequence in context: A298833 A298621 A299587 * A278179 A100748 A072235

Adjacent sequences: A078148 A078149 A078150 * A078152 A078153 A078154

KEYWORD

easy,nonn

AUTHOR

Labos Elemer, Nov 26 2002

STATUS

approved