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A373730
Reduced Collatz function R applied to the numbers 6n+1: a(n) = R(6n+1), where R(k) = (3k+1)/2^r, with r as large as possible.
2
1, 11, 5, 29, 19, 47, 7, 65, 37, 83, 23, 101, 55, 119, 1, 137, 73, 155, 41, 173, 91, 191, 25, 209, 109, 227, 59, 245, 127, 263, 17, 281, 145, 299, 77, 317, 163, 335, 43, 353, 181, 371, 95, 389, 199, 407, 13, 425, 217, 443, 113, 461, 235, 479, 61, 497, 253, 515
OFFSET
0,2
FORMULA
a(n) = A000265(A017185(n)).
MATHEMATICA
A373730[n_] := #/2^IntegerExponent[#, 2] & [9*n + 2];
Array[A373730, 100, 0] (* Paolo Xausa, Aug 19 2024 *)
PROG
(PARI) a(n) = n=9*n+2; n>>valuation(n, 2);
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Jonas Kaiser, Jun 17 2024
STATUS
approved