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%I #29 Apr 05 2021 20:41:19
%S 12,13,15,17,111,113,117,119,123,129,131,137,141,143,147,153,159,161,
%T 167,171,173,179,183,189,197,1101,1103,1107,1109,1113,1127,1131,1137,
%U 1139,1149,1151,1157,1163,1167,1173,1179,1181,1191,1193,1197,1199,1211
%N Prime numbers prefixed with a '1'.
%C Replace every prime by the concatenation of its divisors. [_Lekraj Beedassy_, May 29 2009]
%H David F. Marrs, <a href="/A039790/b039790.txt">Table of n, a(n) for n = 1..10000</a>
%H Kevin N. Stone, <a href="https://web.archive.org/web/20190613194636/https://www.brainbashers.com/showpuzzles.asp?puzzle=ZBLZ">What number comes next in this sequence</a>, BrainBashers [Archived copy at the Wayback Machine].
%F a(n) = A037278(A000040(n)). [_Lekraj Beedassy_, May 29 2009]
%t Array[10^Floor[1 + Log10[#]] + # &@ Prime[#] &, 47] (* _Michael De Vlieger_, Apr 05 2021 *)
%o (PARI) a(n) = eval(concat(Str(1), Str(prime(n)))) \\ _Felix Fröhlich_, Apr 05 2021
%Y Cf. A000040, A037278, A289866 (terms which are prime).
%K nonn,base,dumb
%O 1,1
%A Kevin N. Stone (kevin.stone(AT)brainbashers.com)
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