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 A192010 The smallest number with n digits in its prime factorization (total count of digits of all bases and exponents). 2
 1, 4, 12, 36, 132, 396, 1716, 5148, 25740, 87516, 437580, 1662804, 8314020, 38244492, 167943204, 839716020, 3862693692, 17298150012, 86490750060, 397857450276, 1850902051284, 9254510256420, 42570747179532, 201748323589956, 1008741617949780, 4640211442568988 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS A050252(a(n)) = n and A050252(m) <> n for m < a(n); LINKS EXAMPLE a(2) = 4 = 2^2 and A050252(12) = (1+1) = 2; a(3) = 12 = 2^2 * 3 and A050252(12) = (1+1) + 1 = 3; a(4) = 36 = 2^2 * 3^2 and A050252(36) = (1+1) + (1+1) = 4; a(5) = 132 = 2^2 * 3 * 11 and A050252(132) = (1+1) + 1 + 2 = 5; a(6) = 396 = 2^2 * 3^2 * 11 and A050252(396) = (1+1) + (1+1) + 2 = 6; a(7) = 1716 = 2^2 * 3 * 11 * 13 and A050252(1716) = (1+1) + 1 + 2 + 2 = 7; a(8) = 5148 = 2^2 * 3^2 * 11 * 13 and A050252(5148) = (1+1) + (1+1) + 2 + 2 = 8; a(9) = 25740 = 2^2 * 3^2 * 5 * 11 * 13 and A050252(25740) = (1+1) + (1+1) + 1 + 2 + 2 = 9; a(10) = 87516 = 2^2 * 3^2 * 11 * 13 * 17 and A050252(87516) = (1+1) + (1+1) + 2 + 2 + 2 = 10; a(11) = 437580 = 2^2 * 3^2 * 5 * 11 * 13 * 17 and A050252(437580) = (1+1) + (1+1) + 1 + 2 + 2 + 2 = 11; a(12) = 1662804 = 2^2 * 3^2 * 11 * 13 * 17 * 19 and A050252(1662804) = (1+1) + (1+1) + 2 + 2 + 2 + 2 = 12; a(13) = 8314020 = 2^2 * 3^2 * 5 * 11 * 13 * 17 * 19 and A050252(8314020) = (1+1) + (1+1) + 1 + 2 + 2 + 2 + 2 = 13. PROG (Haskell) import Data.List (elemIndex) import Data.Maybe (fromJust) a192010 n = succ \$ fromJust \$ elemIndex n \$ map a050252 [1..] CROSSREFS Sequence in context: A113990 A231179 A331717 * A252697 A056383 A293857 Adjacent sequences:  A192007 A192008 A192009 * A192011 A192012 A192013 KEYWORD nonn,base AUTHOR Reinhard Zumkeller, Jun 21 2011 EXTENSIONS a(14)-a(26) from Donovan Johnson, Jul 03 2011 STATUS approved

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Last modified October 1 11:59 EDT 2020. Contains 337443 sequences. (Running on oeis4.)