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 A262996 Ten-digit semiprimes with exactly one 1, two 2's, three 3's and four 4's. 1
 1223444433, 1224343443, 1233444243, 1233444423, 1234424343, 1234442343, 1243344243, 1243442433, 1244332443, 1244343423, 1244344323, 1244442333, 1323442443, 1324244433, 1324344423, 1324443243, 1324443423, 1324444323, 1332244443, 1334244243, 1334244423, 1334424243, 1342443243, 1343242443 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS From total 10!/(2!*3!*4!)=12600 ten-digit numbers with exactly one 1, two 2's, three 3's and four 4's, exactly 732 numbers are semiprimes of the form 3*prime. LINKS Zak Seidov, Table of n, a(n) for n = 1..732 MATHEMATICA Select[(FromDigits[#] & /@ Permutations[{1, 2, 2, 3, 3, 3, 4, 4, 4, 4}]), PrimeQ[#/3] &] PROG (PARI) forprime(p=407814811, 1481443741, d=digits(3*p); if(vecsort(d)==[1, 2, 2, 3, 3, 3, 4, 4, 4, 4], print1(3*p", "))) \\ Charles R Greathouse IV, Sep 24 2015 CROSSREFS Cf. A022915. Sequence in context: A119333 A309227 A195988 * A022250 A344365 A211770 Adjacent sequences:  A262993 A262994 A262995 * A262997 A262998 A262999 KEYWORD nonn,base,fini,full AUTHOR Zak Seidov, Oct 07 2015 STATUS approved

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Last modified November 26 21:07 EST 2021. Contains 349344 sequences. (Running on oeis4.)