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A053236
Numbers n such that A053230(n) = 4.
8
23, 54, 59, 84, 114, 138, 149, 172, 177, 232, 257, 281, 293, 311, 355, 392, 417, 422, 434, 445, 481, 506, 561, 596, 601, 644, 656, 686, 715, 745, 763, 775, 798, 809, 853, 864, 944, 955, 979, 984, 1013, 1018, 1061, 1072, 1140, 1164, 1187, 1192, 1222, 1227
OFFSET
1,1
LINKS
MAPLE
with(numtheory): f := [seq( `if`((sigma(i+1) > sigma(i)), i, print( )), i=1..8000)];
seq( `if`(f[i+1] - f[i] = 4, i, print( )), i=1..3000);
PROG
(Haskell)
import Data.List (elemIndices)
a053236 n = a053236_list !! (n-1)
a053236_list = map (+ 1) $ elemIndices 4 a053230_list
-- Reinhard Zumkeller, May 07 2012
KEYWORD
nonn
AUTHOR
Asher Auel, Jan 10 2000
STATUS
approved