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Numbers n such that A053238(n) = 3.
7

%I #7 Oct 27 2023 22:00:45

%S 154,200,259,340,375,466,554,569,673,688,779,869,884,912,989,1095,

%T 1232,1276,1394,1409,1493,1513,1630,1645,1719,1805,1819,1923,2027,

%U 2042,2117,2153,2162,2208,2240,2345,2480,2542,2662,2706,2850,2871,2886,3003,3078

%N Numbers n such that A053238(n) = 3.

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

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

%Y Cf. A000203, A053226, A053238, A053239, A053240, A053241, A053242, A053244, A053245.

%K nonn

%O 1,1

%A _Asher Auel_, Jan 10 2000