A333234 - OEIS

%I #17 Jul 31 2022 13:57:04

%S 20,40,34,64,76,84,200,106,300,118,210,270,248,124,140,324,221,231,

%T 261,338,150,170,186,364,384,341,390,371,424,451,161,481,506,511,548,

%U 570,600,551,581,611,628,636,656,664,688,714,694,749,721,750,794

%N Nonprimes describing the nonprime digits' positions in a way explained in the Comments section.

%C "20" must be read: "At position 2, there is a 0". And indeed, there is, when considering the sequence as a string of concatenated digits;

%C "40" reads: "At position 4, there is a 0" - which is true;

%C "34" reads: "At position 3, there is a 4" - which is also true;

%C ...

%C "200" reads: "At position 20, there is a 0" - which is true (the central 0 in 300); etc.

%H Carole Dubois, <a href="/A333234/b333234.txt">Table of n, a(n) for n = 1..4103</a>

%Y Cf. A264646.

%K base,nonn

%O 1,1

%A _Eric Angelini_ and _Carole Dubois_, Mar 12 2020