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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A329711 Numbers n such that n = prime(d_1) * prime(d_2) * ... * prime(d_k), where n is a concatenation of d_1, d_2, ..., d_k.

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%I A329711 #47 May 04 2022 17:13:34
%S A329711 14,154,1196,2127,61411,172482,223227,279174,291318,1233822,1346235,
%T A329711 2681318,3127010,6541482,9105217,14216826,15136418,15454362,17211896,
%U A329711 22442133,24174129,32693925,35219085,35523825,51157348,51431138,57121662,58935162,91242978,101721214
%N A329711 Numbers n such that n = prime(d_1) * prime(d_2) * ... * prime(d_k), where n is a concatenation of d_1, d_2, ..., d_k.
%H A329711 Giovanni Resta, <a href="/A329711/b329711.txt">Table of n, a(n) for n = 1..191</a>
%H A329711 Bartlomiej Pawlik, <a href="/A329711/a329711_1.txt">Table of concatenations and prime factorizations of a(n) for n = 1..191</a>
%e A329711 14 = prime(1)*prime(4) = 2*7, so 14 is a term.
%e A329711 154 = prime(1)*prime(5)*prime(4) = 2*11*7, so 154 is a term.
%e A329711 2127 = prime(2)*prime(127) = 3*709, so 2127 is a term.
%e A329711 9105217 = prime(9)*prime(10)*prime(5)*prime(21)*prime(7), so 9105217 is a term.
%t A329711 ok[n_] := Block[{d = DigitCount@ n}, AllTrue[Range@ 9, IntegerExponent[n, Prime@ #] <= d[[#]] &]]; ric[v_, d_] := If[PrimeQ@ v, PrimePi@ v == FromDigits@ d, Block[ {r=False, p, m = Length@ d}, Do[ If[ d[[i + 1]] > 0, p = Prime@ FromDigits@ Take[d, i]; If[Mod[v, p] == 0 && (r = ric[v/p, Take[d, i - m]]), Break[]]], {i, m - 1}]; r]]; Select[ Range@ 300000, If[ok@# && ric[#, IntegerDigits@ #], Print@#; True, False] &] (* _Giovanni Resta_, Mar 12 2020 *)
%Y A329711 Cf. A097227 (a subsequence), A318298.
%K A329711 nonn,base
%O A329711 1,1
%A A329711 _Bartlomiej Pawlik_, Mar 07 2020
%E A329711 More terms from _Giovanni Resta_, Mar 12 2020