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Least prime signature numbers that are not a Jordan-Polya number.
2

%I #10 Jan 02 2021 04:50:42

%S 30,60,180,210,360,420,840,900,1080,1260,1680,1800,2160,2310,2520,

%T 3360,3600,4620,5400,6300,6480,6720,7200,7560,9240,10800,12600,12960,

%U 13440,13860,15120,18480,21600,25200,26880,27000,27720,30030,32400,36960

%N Least prime signature numbers that are not a Jordan-Polya number.

%H Amiram Eldar, <a href="/A064783/b064783.txt">Table of n, a(n) for n = 1..10000</a>

%e a(1)= 30 since 30 is a least prime signature (cf. A025487) but is not the product of factorial numbers (cf. A001013).

%Y Cf. A000142, A001013, A025487.

%K easy,nonn

%O 1,1

%A _Alford Arnold_, Oct 19 2001

%E More terms from _Naohiro Nomoto_ and _Don Reble_, Oct 21 2001

%E Offset corrected by _Amiram Eldar_, Jan 02 2021