A227982 Numbers n such that sigma(n+1) - sigma(n-1) > sigma(n); where sigma(n) = A000203(n) = sum of the divisors of n.

47, 59, 83, 107, 119, 143, 167, 179, 215, 239, 251, 263, 299, 335, 359, 383, 395, 419, 431, 467, 479, 503, 527, 539, 587, 599, 623, 629, 647, 659, 671, 719, 755, 767, 779, 839, 863, 887, 899, 923, 935, 959, 983, 1007, 1019, 1055, 1079, 1091, 1103, 1139, 1175

Offset: 1

Author

Jaroslav Krizek, Aug 08 2013

Keywords

• nonn

Comments

See A076530 - numbers n such that sigma(n+1) - sigma(n-1) = sigma(n).

Complement of union of A076530, A227983 and number 1.

Examples

			Number 59 is in the sequence because sigma(60) - sigma(58) = 168 - 90 = 78 > sigma(59) = 60.
		

Links

• Jaroslav Krizek, Table of n, a(n) for n = 1..2000

Crossrefs

Cf. A076530, A000203, A227983.

Programs

Mathematica

Flatten[Position[Partition[DivisorSigma[1,Range[1200]],3,1],?(Last[#]- First[#]> #[[2]]&),{1},Heads->False]]+1 (* _Harvey P. Dale, Mar 31 2014 *)