A163401 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.
487856, 694103, 771084, 836254, 1051886, 1119347, 1122734, 1157014, 1181077, 1591742, 1638820, 1646819, 1820743, 1921148, 1945355, 2001782, 2026571
Offset: 1
Examples
m=487856 is in the sequence because 4878561, 4878563, 4878567, 4878569 from attachment of d_1 = 1 to 9, and 48785611, 48785613, .., 48785697, 48785699 from attachment of d_2 = 11 to 99, and 487856111, 487856113,..., 487856997, 487856999 from attachment of d_3=111 to 999 are all composite.
Crossrefs
Cf. A002808.
Extensions
13 more terms from R. J. Mathar, Aug 07 2009
Comments