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 A114321 Difference between first odd semiprime > 11^n and 11^n. 0
 8, 4, 2, 2, 6, 14, 4, 6, 6, 6, 4, 6, 32, 14, 10, 2, 12, 2, 2, 12, 36, 6, 28, 6, 12, 32, 8, 12, 28, 24, 48 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 COMMENTS A098147 is difference between first odd semiprime > 10^n and 10^n. LINKS FORMULA a(n) = minimum integer k such that 11^n + k is an element of A046315. a(n) = minimum integer k such that A001020(n) + k is an element of A046315. EXAMPLE a(0) = 8 because 11^0 + 8 = 9 = 3^2 is an odd semiprime. a(1) = 4 because 11^1 + 4 = 15 = 3 * 5 is an odd semiprime. a(2) = 2 because 11^2 + 2 = 123 = 3 * 41. a(3) = 2 because 11^3 + 2 = 1333 = 31 * 43 (brilliant). a(4) = 6 because 11^4 + 6 = 14647 = 97 * 151. a(5) = 14 because 11^5 + 14 = 161065 = 5 * 32213. a(6) = 4 because 11^6 + 4 = 1771565 = 5 * 354313. a(7) = 6 because 11^7 + 6 = 19487177 = 41 * 475297. a(8) = 6 because 11^8 + 6 = 214358887 = 317 * 676211. a(9) = 6 because 11^9 + 6 = 2357947697 = 7 * 336849671. a(10) = 4 because 11^10 + 4 = 25937424605 = 5 * 5187484921. a(30) = 48 because 11^30 + 48 = 17449402268886407318558803753849 = 7 * 2492771752698058188365543393407. CROSSREFS Cf. A001020, A001358, A098147. Sequence in context: A131606 A033328 A097529 * A154434 A222301 A198353 Adjacent sequences:  A114318 A114319 A114320 * A114322 A114323 A114324 KEYWORD easy,nonn AUTHOR Jonathan Vos Post, Feb 05 2006 STATUS approved

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Last modified September 26 15:47 EDT 2021. Contains 347668 sequences. (Running on oeis4.)