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A015872 Numbers k such that phi(k + 6) | sigma(k) + 6. 0
10, 20, 26, 58, 122, 1018, 1040, 2042, 8186, 32762, 522752, 2097146, 8388602, 9898496, 16871744, 33554426, 1073741818, 1630145024 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(19) > 10^12. - Donovan Johnson, Feb 28 2012

LINKS

Table of n, a(n) for n=1..18.

MATHEMATICA

Select[Range[100000],

Divisible[DivisorSigma[1, #] + 6, EulerPhi[# + 6]] &] (* David Nacin, Feb 2012 *)

CROSSREFS

Sequence in context: A229305 A229304 A101869 * A019491 A249989 A175229

Adjacent sequences:  A015869 A015870 A015871 * A015873 A015874 A015875

KEYWORD

nonn

AUTHOR

Robert G. Wilson v

EXTENSIONS

Offset corrected and a(10)-a(18) from Donovan Johnson, Feb 28 2012

STATUS

approved

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Last modified December 2 11:59 EST 2021. Contains 349440 sequences. (Running on oeis4.)