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A247948 Five-digit odd semiprimes with all digits distinct. 1

%I #14 Nov 20 2014 17:58:40

%S 10237,10239,10249,10265,10279,10297,10327,10345,10347,10349,10367,

%T 10379,10389,10397,10423,10435,10473,10483,10489,10493,10495,10497,

%U 10523,10537,10543,10547,10573,10579,10583,10587,10623,10637,10643,10645,10649

%N Five-digit odd semiprimes with all digits distinct.

%C There are exactly 4858 five-digit odd semiprimes with all digits distinct. The last few terms of the sequence are: 98501, 98503, 98517, 98521, 98531, 98537, 98567, 98603, 98607, 98617, 98635, 98647, 98653, 98657, 98671, 98701, 98723, 98741, 98743, 98751, 98765.

%C See the link with the b-file for all 4858 entries.

%H K. D. Bajpai, <a href="/A247948/b247948.txt">Table of n, a(n) for n = 1..4858</a>

%e a(1) = 10237 = 29 * 353 is the smallest five-digit odd semiprime with all digits distinct.

%e a(4858) = 98765 = 5 * 19753 is the largest five-digit odd semiprime with all digits distinct.

%t c = 0; Do[If[Length[Union[IntegerDigits[n]]] == 5 && PrimeOmega[n] == 2, c++; Print[c, " ", n]], {n, 10001, 99999, 2}]

%Y Cf. A001358, A046315, A074671, A074673, A235690, A247947.

%K nonn,base,fini,full

%O 1,1

%A _K. D. Bajpai_, Sep 27 2014

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