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 A057534 a(n+1) = a(n)/2 if 2|a(n), a(n)/3 if 3|a(n), a(n)/5 if 5|a(n), a(n)/7 if 7|a(n), a(n)/11 if 11|a(n), a(n)/13 if 13|a(n), else 17*a(n)+1. 14
 61, 1038, 519, 173, 2942, 1471, 25008, 12504, 6252, 3126, 1563, 521, 8858, 4429, 75294, 37647, 12549, 4183, 71112, 35556, 17778, 8889, 2963, 50372, 25186, 12593, 1799, 257, 4370, 2185, 437, 7430, 3715, 743, 12632, 6316, 3158, 1579, 26844, 13422 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 COMMENTS This is the `17x+1' map. The `Px+1 map': if x is divisible by any prime < P then divide out these primes one at a time starting with the smallest; otherwise multiply x by P and add 1. REFERENCES Murad A. AlDamen, Smarandache Notion Journal, "Murad iterating function" [details?]. Murad A. AlDamen, Murad iterating function, Journal of University of Jerash, 2001, to appear. LINKS Eric Weisstein's World of Mathematics, Collatz problem MAPLE with(numtheory): a := proc(n) option remember: local k; if n=0 then RETURN(61); fi: for k from 1 to 6 do if a(n-1) mod ithprime(k) = 0 then RETURN(a(n-1)/ithprime(k)); fi: od: RETURN(17*a(n-1)+1) end: CROSSREFS Cf. A057446, A057216 (short version), A057522, A057614. Sequence in context: A317283 A264306 A138790 * A152868 A218112 A154428 Adjacent sequences:  A057531 A057532 A057533 * A057535 A057536 A057537 KEYWORD nonn,easy AUTHOR Murad A. AlDamen (Divisibility(AT)yahoo.com), Oct 17 2000 EXTENSIONS More terms from James A. Sellers and Larry Reeves (larryr(AT)acm.org), Oct 18 2000 STATUS approved

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Last modified November 29 08:47 EST 2020. Contains 338762 sequences. (Running on oeis4.)