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A053235 Numbers n such that A053230(n) = 3. 8
158, 202, 263, 350, 387, 476, 567, 582, 701, 790, 879, 894, 926, 999, 1103, 1236, 1282, 1403, 1418, 1501, 1523, 1646, 1661, 1737, 1831, 1847, 1953, 2059, 2074, 2149, 2185, 2237, 2265, 2370, 2505, 2563, 2683, 2729, 2873, 2894, 2909, 3032, 3107, 3127 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

MAPLE

with(numtheory): f := [seq( `if`((sigma(i+1) > sigma(i)), i, print( )), i=1..5000)];

seq( `if`(f[i+1] - f[i] = 3, i, print( )), i=1..1000);

MATHEMATICA

Position[Differences@ Select[Range[10^4], Less @@ DivisorSigma[1, # + {0, 1}] &], 3][[All, 1]] (* Michael De Vlieger, Nov 19 2019 *)

PROG

(Haskell)

import Data.List (elemIndices)

a053235 n = a053235_list !! (n-1)

a053235_list = map (+ 1) $ elemIndices 3 a053230_list

-- Reinhard Zumkeller, May 07 2012

CROSSREFS

Cf. A000203, A053224, A053230, A053231, A053232, A053233, A053234, A053236, A053237.

Sequence in context: A048930 A130864 A045245 * A255351 A088728 A258960

Adjacent sequences:  A053232 A053233 A053234 * A053236 A053237 A053238

KEYWORD

nonn

AUTHOR

Asher Auel (asher.auel(AT)reed.edu), Jan 10 2000

STATUS

approved

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Last modified November 28 04:43 EST 2021. Contains 349400 sequences. (Running on oeis4.)