A231545 - OEIS

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A231545

Numbers n such that n = sigma(n) - sigma(n-1).

3

2, 6, 8586, 16120, 29886160

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

OFFSET

1,1

COMMENTS

Also, numbers n such that antisigma(n) = antisigma(n-1), where antisigma(n) = A024816(n) = the sum of the non-divisors of n that are between 1 and n.

Numbers n such that A163553(n-1) = 0.

LINKS

Table of n, a(n) for n=1..5.

FORMULA

a(n) = A067816(n) + 1.

EXAMPLE

6 is in sequence because antisigma(6) = antisigma(5) = 9.

CROSSREFS

Cf. A067816, A024816 (antisigma(n)), A231546 (numbers n such that sigma(n) = sigma(n-1)).

Sequence in context: A357193 A355556 A162146 * A055698 A121167 A115658

Adjacent sequences: A231542 A231543 A231544 * A231546 A231547 A231548

KEYWORD

nonn

AUTHOR

Jaroslav Krizek, Nov 11 2013

STATUS

approved