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%I #20 Oct 11 2021 18:44:04
%S 0,1,12,21,22422,24223,33333,34441524,4242436235,23443535352,
%T 34462443242,35256523324,4341535435353,4645441523344,5244526446515,
%U 5335524234335
%N k-digit numbers whose digit(s) are the number of distinct prime factors in each of the following k integers.
%C a(9) = 4242436235 found by _Carlos Rivera_.
%C a(17) > 10^13. - _Giovanni Resta_, Jan 04 2019
%H Chris Caldwell and G. L. Honaker, Jr, <a href="https://primes.utm.edu/curios/page.php?short=24223">Prime Curio for 24223</a>
%e 21 is a term because 21 is a 2-digit number and its digits (2,1) are the number of distinct prime factors in each of the following 2 integers; i.e., 22 = 2*11 (two distinct prime factors) and 23 = 23 (one distinct prime factor), therefore (2,1) -> 21.
%o (PARI) isok(m) = {my(d=digits(m)); for (i=1, #d, if (d[i] != omega(m+i), return(0));); return (1);} \\ _Michel Marcus_, Oct 11 2021
%Y Cf. A000040, A001221, A323084.
%K nonn,base,more
%O 1,3
%A _G. L. Honaker, Jr._, Jan 03 2019
%E a(10)-a(16) from _Giovanni Resta_, Jan 04 2019