A380391 - OEIS

%I #20 Jan 25 2025 12:39:25

%S 10,12,14,16,18,20,28,30,31,32,34,35,36,38,40,42,50,51,52,54,56,60,62,

%T 64,68,70,71,72,73,74,75,76,78,80,84,85,90,91,92,93,94,95,96,97,98,

%U 100,101,102,103,104,105,106,107,108,109,110,112,114,115,116,118,119,120

%N Numbers k such that A343750(k) != k.

%e k = 13: A343750(13) = 13, thus k = 13 is not in the sequence.

%e k = 14: A343750(14) = 41, thus k = 14 is a term.

%t q[k_] := Module[{perm = FromDigits /@ Permutations[IntegerDigits[k]], d}, d = DivisorSigma[0, perm]; Min@ perm[[Position[d, Min[d]] // Flatten]] != k]; Select[Range[120], q] (* _Amiram Eldar_, Jan 24 2025 *)

%Y Cf. A000005, A004719, A010785, A272215, A343750.

%K nonn,base

%O 1,1

%A _Ctibor O. Zizka_, Jan 23 2025