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Members of A055932 which are not least prime signatures (cf. A025487).
10

%I #9 Feb 02 2024 09:05:09

%S 18,54,90,108,150,162,270,300,324,450,486,540,600,630,648,750,810,972,

%T 1050,1200,1350,1458,1470,1500,1620,1890,1944,2100,2250,2400,2430,

%U 2700,2916,2940,3000,3150,3240,3750,3780,3888,4050,4200,4374,4410,4500,4800

%N Members of A055932 which are not least prime signatures (cf. A025487).

%H Michael De Vlieger, <a href="/A056808/b056808.txt">Table of n, a(n) for n = 1..10000</a>

%F {a(n) : n >= 1} = {A057335(A335485(k)) : k >= 1}. - _Peter Munn_, Feb 02 2024

%e 18 = 2*3*3 and all prime divisors are consecutive primes but the least prime signature is 12 = 2*2*3; so a(1) = 18.

%t With[{nn = 4800}, Select[Range[2, nn], And[#1 != Times @@ MapIndexed[Prime[First@ #2]^#1 &, Sort[#3, Greater]], Last[#2] == Prime@ Length[#2]] & @@ Apply[Join, {{#1}, Transpose@ #2}] & @@ {#, FactorInteger[#]} &] ] (* _Michael De Vlieger_, Feb 06 2020 *)

%Y Cf. A025487, A055932, A057335, A335485.

%K easy,nonn

%O 1,1

%A _Alford Arnold_, Aug 22 2000

%E More terms from Larry Reeves (larryr(AT)acm.org), Nov 28 2000