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%I #13 Oct 27 2023 22:00:45
%S 23,54,59,84,114,138,149,172,177,232,257,281,293,311,355,392,417,422,
%T 434,445,481,506,561,596,601,644,656,686,715,745,763,775,798,809,853,
%U 864,944,955,979,984,1013,1018,1061,1072,1140,1164,1187,1192,1222,1227
%N Numbers n such that A053230(n) = 4.
%H Reinhard Zumkeller, <a href="/A053236/b053236.txt">Table of n, a(n) for n = 1..10000</a>
%p with(numtheory): f := [seq( `if`((sigma(i+1) > sigma(i)),i,print( )), i=1..8000)];
%p seq( `if`(f[i+1] - f[i] = 4,i,print( )), i=1..3000);
%o (Haskell)
%o import Data.List (elemIndices)
%o a053236 n = a053236_list !! (n-1)
%o a053236_list = map (+ 1) $ elemIndices 4 a053230_list
%o -- _Reinhard Zumkeller_, May 07 2012
%Y Cf. A000203, A053224, A053230, A053231, A053232, A053233, A053234, A053235, A053237.
%K nonn
%O 1,1
%A _Asher Auel_, Jan 10 2000