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A262149
Rocket sequence 50: a(0)=50, a(n)=A073846(a(n-1)).
2
50, 97, 68, 139, 94, 211, 140, 349, 222, 607, 378, 1129, 689, 427, 272, 769, 476, 1493, 901, 552, 1783, 1072, 3863, 2268, 9151, 5275, 3077, 1819, 1092, 3931, 2308, 9323, 5370, 24113, 13671, 7825, 4528, 20021, 11385, 6537, 3796, 16363, 9336, 44927, 25250
OFFSET
0,1
COMMENTS
This sequence has been checked up to a(98) = 1078406742163 without reaching 50. It seems to be slowly climbing in value in both the negative and positive directions. Hence, its period is either extremely large or, as I conjecture, infinite. Thus I dubbed the sequence "Rocket" because, as opposed the "Hailstone" sequences, it never seems to "fall".
This sequence, when extended to all integers using a(n-1) = A073898(a(n)), is R#(50), see A073846 for definition. - Chayim Lowen, Jan 25 2016
LINKS
FORMULA
a(n+1) = A073846(a(n)).
a(n-1) = A073898(a(n)).
EXAMPLE
a(1) = A073846(a(0)) = A073846(50) = 97.
MATHEMATICA
s = Module[{p = Prime@ Range@ PrimePi@ #, c}, c = Complement[Range@ #, p]; Riffle[Take[c, Length@ p], p]] &[5*10^5]; NestList[s[[#]] &, 50, 44] (* Michael De Vlieger, Jan 27 2016, after Harvey P. Dale at A073846 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Chayim Lowen, Sep 12 2015
EXTENSIONS
Missing term 1092 inserted by Chayim Lowen, Mar 26 2017
STATUS
approved