A336938 The maximum values of the sets A(n), where A(0) = {0} and A(n+1) is the union of A(n) and the Collatz orbit of the smallest natural number missing in A(n).

0, 4, 16, 16, 52, 52, 52, 160, 160, 160, 160, 160, 160, 9232, 9232, 9232, 9232, 9232, 9232, 9232, 9232, 9232, 9232, 9232, 9232, 9232, 9232, 9232, 9232, 9232, 9232, 9232, 9232, 9232, 9232, 9232, 9232, 9232, 9232, 9232, 9232, 9232, 9232, 9232, 9232, 9232, 9232

Offset: 0

Author

Markus Sigg, Aug 08 2020

Keywords

• nonn

Crossrefs

Cf. A061641, A336256.

Programs

PARI

firstMiss(A) = { my(i); if(#A == 0 || A[1] > 0, return(0)); for(i = 1, A[#A] + 1, if(!setsearch(A, i), return(i))); };
iter(A) = { my(a = firstMiss(A)); while(!setsearch(A, a), A = setunion(A, Set([a])); a = if(a % 2, 3*a+1, a/2)); A; };
makeVec(m) = { my(v = [], A = Set([0]), i); for(i = 1, m, v = concat(v, A[#A]); if (i < m, A = iter(A))); v; };
makeVec(47)