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 A320229 Least semiprime from merging n consecutive semiprimes. 0
 4, 46, 469, 25263334, 910141521, 469101415, 26333435383946, 3334353839464951, 91014152122252633, 65697477828586879193, 778285868791939495106111, 778285868791939495106111115118, 115118119121122123129133134141142143, 3538394649515557586265697477 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Apparently a(n) exists for any n. LINKS EXAMPLE n = 14: 35-38-39-46-49-51-55-57-58-62-65-69-74-77 => 1540961*2296225958681340790757, n = 15: 87-91-93-94-95-106-111-115-118-119-121-122-123-129-133 => 53*165885650851058700285247530587209870361, n = 16: 6-9-10-14-15-21-22-25-26-33-34-35-38-39-46-49 => 43669*15823906023088521224290421. PROG (Perl) use ntheory ":all"; sub ls { my(\$n, \$k, \$s)=(shift, 0, 0); do { \$k++; \$s = fromdigits(join "", map { nth_semiprime(\$_) } \$k .. \$k+\$n-1); } until is_semiprime(\$s); \$s; } print "\$_ ", ls(\$_), "\n" for 1..30; # Dana Jacobsen, Oct 19 2018 CROSSREFS Sequence in context: A132932 A231787 A173716 * A097952 A097643 A155652 Adjacent sequences:  A320226 A320227 A320228 * A320230 A320231 A320232 KEYWORD nonn,base AUTHOR Zak Seidov, Oct 08 2018 STATUS approved

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Last modified June 12 06:52 EDT 2021. Contains 344943 sequences. (Running on oeis4.)