

A053226


n for which sigma(n) > sigma(n+1).


12



4, 6, 8, 10, 12, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 45, 46, 48, 50, 52, 54, 56, 58, 60, 64, 66, 68, 70, 72, 76, 78, 80, 82, 84, 86, 88, 90, 92, 94, 96, 98, 100, 102, 104, 105, 106, 108, 110, 112, 114, 116, 117, 118, 120, 122, 124, 126, 128, 130
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OFFSET

1,1


LINKS

T. D. Noe, Table of n, a(n) for n = 1..1000


MAPLE

with(numtheory): seq( `if`((sigma(i) > sigma(i+1)), i, print( )), i=1..139);


MATHEMATICA

Select[Range[150], DivisorSigma[1, #] > DivisorSigma[1, # + 1] &] (* Carl Najafi, Aug 16 2011 *)


PROG

(Haskell)
import Data.List (findIndices)
a053226 n = a053226_list !! (n1)
a053226_list = map (+ 1) $ findIndices (< 0) a053222_list
 Reinhard Zumkeller, Oct 16 2011
(PARI) is(n)=sigma(n)>sigma(n+1) \\ Charles R Greathouse IV, Mar 09 2014


CROSSREFS

Cf. A000203, A053222, A053224, A053238.
Sequence in context: A193167 A020645 A051756 * A227112 A074827 A068354
Adjacent sequences: A053223 A053224 A053225 * A053227 A053228 A053229


KEYWORD

nonn


AUTHOR

Asher Auel (asher.auel(AT)reed.edu) Jan 06 2000


STATUS

approved



