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A037198 Number of divisors of (sigma(n)-n) = number of divisors of n. 1
6, 9, 10, 14, 22, 28, 30, 33, 38, 42, 46, 51, 54, 60, 62, 66, 69, 84, 86, 87, 91, 92, 93, 96, 102, 118, 132, 133, 135, 141, 142, 145, 158, 159, 166, 168, 170, 174, 182, 183, 188, 190, 206, 216, 217, 219, 246, 247, 248, 249, 253, 262, 264, 267, 278, 280, 285, 290 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..1000

MATHEMATICA

Select[Range[400], DivisorSigma[0, DivisorSigma[1, #]-#]==DivisorSigma[ 0, #]&] (* Harvey P. Dale, Feb 24 2017 *)

PROG

(PARI) isok(n) = (diff = sigma(n)-n) && (numdiv(n) == numdiv(diff)) \\ Michel Marcus, Jul 14 2013

CROSSREFS

Sequence in context: A337287 A145311 A328244 * A054020 A121014 A153519

Adjacent sequences:  A037195 A037196 A037197 * A037199 A037200 A037201

KEYWORD

easy,nonn

AUTHOR

Naohiro Nomoto

STATUS

approved

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Last modified September 23 12:53 EDT 2020. Contains 337310 sequences. (Running on oeis4.)