1,1

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.

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

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

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

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

Sequence in context: A114045 A116899 A162146 * A055698 A121167 A115658

Adjacent sequences: A231542 A231543 A231544 * A231546 A231547 A231548

nonn

Jaroslav Krizek, Nov 11 2013

approved