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Numbers m such that all 10*m+d_1, 100*m+d_2 and 1000*m+d_3 are composite, where d_i are any i-digit numbers of A136333.
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%I #6 Jan 15 2018 15:46:58

%S 487856,694103,771084,836254,1051886,1119347,1122734,1157014,1181077,

%T 1591742,1638820,1646819,1820743,1921148,1945355,2001782,2026571

%N Numbers m such that all 10*m+d_1, 100*m+d_2 and 1000*m+d_3 are composite, where d_i are any i-digit numbers of A136333.

%C A subsequence A163398 satisfying an additional requirement on the 1000*m+d_3 compositions.

%e m=487856 is in the sequence because 4878561, 4878563, 4878567, 4878569 from attachment of

%e d_1 = 1 to 9, and 48785611, 48785613, .., 48785697, 48785699 from attachment of

%e d_2 = 11 to 99, and 487856111, 487856113,..., 487856997, 487856999 from

%e attachment of d_3=111 to 999 are all composite.

%Y Cf. A002808.

%K nonn,base

%O 1,1

%A Vladislav-Stepan Malakhovsky and _Juri-Stepan Gerasimov_, Jul 26 2009

%E 13 more terms from _R. J. Mathar_, Aug 07 2009