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A175730 Numbers with deficiency of 42. 0
43, 69, 99, 165, 1168, 1365, 2139136, 32062485, 33722368, 132701205, 8592621568 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Numbers with an abundance of -42.

7454198513685 is also in the sequence. - Alexander Violette, Jan 10 2021

Numbers of the form 2^k * (2^(k + 1) + 41) are in the sequence if and only if 2^(k + 1) + 41 is prime. - David A. Corneth, Jan 15 2021

LINKS

Table of n, a(n) for n=1..11.

PROG

(PARI) for(n=1, 100000000, if(((sigma(n)-2*n)==-42), print1(n, ", ")))

(PARI) is(n)=2*n-sigma(n)==42 \\ Charles R Greathouse IV, Jan 11 2021

(PARI) list(lim)=my(v=List()); forfactored(n=1, lim\1, if(2*n[1]-sigma(n)==42, listput(v, n[1]))); Vec(v) \\ Charles R Greathouse IV, Jan 11 2021

CROSSREFS

Cf. A033879 (deficiency).

Sequence in context: A139875 A174812 A146355 * A087765 A141971 A144974

Adjacent sequences:  A175727 A175728 A175729 * A175731 A175732 A175733

KEYWORD

nonn,more,changed

AUTHOR

Jason G. Wurtzel, Aug 24 2010

EXTENSIONS

a(10) from Jon E. Schoenfield, Jan 13 2021

a(11) from Charles R Greathouse IV, Jan 15 2021

STATUS

approved

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Last modified January 20 04:53 EST 2021. Contains 340301 sequences. (Running on oeis4.)