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 A347652 Records in the trajectory of all positive integers in the 3x+1 or Collatz problem, including the trajectory [1, 4, 2, 1] of 1. 0
 1, 4, 10, 16, 22, 34, 52, 70, 106, 160, 214, 322, 484, 700, 790, 1186, 1780, 2158, 3238, 4858, 7288, 9232, 13120, 17224, 17494, 26242, 39364, 41524, 45682, 68524, 77092, 97576, 98962, 148444, 167002, 250504, 354292, 504466, 756700, 851290, 1276936, 1417174, 2125762 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Replacing the second term (4) with the first two primes (2, 3) we have 1, 2, 3, 10, 16, 22, ... the records in A070165. LINKS EXAMPLE The first three rows of A235795 are [1, 4, 2, 1]; [2, 1]; [3, 10, 5, 16, 8, 4, 2, 1]. The records are [1, 4, 10, 16], the same as a(1)..a(4). PROG (PARI) f(n) = if (n%2, 3*n+1, n/2); \\ A014682 row(n) = {my(list=List()); listput(list, n); until(n==1, n = f(n); listput(list, n)); Vec(list); } \\ A235795 lista(nn) = {my(m=0, list = List()); for (n=1, nn, my(v = row(n)); for (k=1, #v, if (v[k]>m, m=v[k]; listput(list, m); ); )); Vec(list); } \\ Michel Marcus, Sep 10 2021 CROSSREFS Records in A235795. Cf. A006370, A070165, A235800, A347270 (all 3x+1 sequences). Sequence in context: A294636 A295560 A161644 * A215032 A294980 A310534 Adjacent sequences:  A347649 A347650 A347651 * A347653 A347654 A347655 KEYWORD nonn AUTHOR Omar E. Pol, Sep 09 2021 EXTENSIONS More terms from Michel Marcus, Sep 10 2021 STATUS approved

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Last modified December 8 01:25 EST 2021. Contains 349590 sequences. (Running on oeis4.)