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Numbers m for which A139770(m) and A140635(m) differ.
2

%I #16 Aug 31 2023 12:16:18

%S 16,64,81,144,192,320,324,400,448,576,625,704,729,784,832,900,960,

%T 1024,1088,1216,1296,1344,1458,1472,1600,1728,1764,1856,1936,1984,

%U 2025,2112,2240,2304,2368,2401,2496,2500,2624,2704,2752,2880,2916,3008,3072,3136,3264,3392,3520,3600,3645,3648,3776,3904,3969

%N Numbers m for which A139770(m) and A140635(m) differ.

%t (* a139770[ ] and a140635[ ] are defined in their respective sequences *)

%t a365263[{m_, n_}] := Select[Range[m, n], a139770[#]!=a140635[#]&]

%t a365263[{1, 4000}]

%o (PARI) isok(m) = my(nd = numdiv(m)); for (i=1, m-1, if (numdiv(i) == nd, return (0)); if (numdiv(i)> nd, return(1))); 0; \\ _Michel Marcus_, Aug 31 2023

%Y Cf. A000005, A002182, A005179, A007412, A061799, A139770, A140635.

%K nonn

%O 1,1

%A _Hartmut F. W. Hoft_, Aug 29 2023