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 A049074 Ulam's conjecture (steps to return n to 1 after division by 2 and, if needed, multiplication by 3 with 1 added). 2
 8, 3, 49, 7, 36, 55, 288, 15, 339, 46, 259, 67, 119, 302, 694, 31, 214, 357, 519, 66, 148, 281, 633, 91, 658, 145, 101440, 330, 442, 724, 101104, 63, 841, 248, 540, 393, 535, 557, 2344, 106, 101331, 190, 1338, 325, 497, 679, 100979, 139, 806, 708, 1130, 197 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Appeared in School Science and Mathematics in 1982. LINKS Enoch Haga, Problem, School Science and Mathematics, Nov 1983, vol. 83, no 7, page 628. LaBar, Problem #3929, School Science and Mathematics, Dec 1982, vol. 82 no 8, page 715. EXAMPLE Beginning at n=1, algorithm produces s+t+a=8. PROG (This was in the formula section but is clearly a program in some language. - N. J. A. Sloane, Apr 18 2017) n=n+1:a=n\x=n/2\if int(x)=x then e=e+1:n=x:s=s+n: if n=1 then print s+t+a:e=0:o=0:s=0:t=0:n=a:return to n=n+1\if int(x)<>x then o=o+1:y=n*3+1:n=y:t=t+n: if n=1 then print s+t+a:e=0:o=0:s=0:t=0:n=a:return to n=n+1:else return to x=n/2 (Python) def a(n):     if n==1: return 8     l=[n]     while True:         if n%2==0: n//=2         else: n = 3*n + 1         l.append(n)         if n<2: break     return sum(l) print([a(n) for n in range(1, 101)]) # Indranil Ghosh, Apr 14 2017 CROSSREFS Almost the same as A033493. Cf. A049067. Sequence in context: A287645 A182054 A302214 * A286034 A256046 A197245 Adjacent sequences:  A049071 A049072 A049073 * A049075 A049076 A049077 KEYWORD easy,nonn AUTHOR STATUS approved

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Last modified December 4 17:44 EST 2021. Contains 349526 sequences. (Running on oeis4.)