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A247716
Odd numbers n containing 65536 as the highest power of 2 in their Collatz (3x+1) iteration.
1
14563, 17259, 19417, 20455, 21845, 25889, 27273, 30683, 34519, 38835, 40911, 46025, 51779, 54547, 58253, 61367, 64647, 69037, 72729, 77669, 81821, 92049, 92051, 96971, 103557, 107623, 109093, 109095, 122733, 129295, 138077, 143497, 145457, 145459, 153243, 155341, 161435
OFFSET
1,1
COMMENTS
a(n)*2^k also contains 65536 as the highest power of 2 for any k >= 0.
PROG
(PARI)
Max2(n)=v=[n]; while(n!=1, if(n==Mod(0, 2), n=n/2; v=concat(v, n)); if(n==Mod(1, 2)&&n!=1, n=3*n+1; v=concat(v, n))); k=1; while(vecsearch(vecsort(v), 2^k), k++); 2^(k-1)
n=1; while(n<10^4, if(n%2&&Max2(n)==65536, print1(n, ", ")); n++)
CROSSREFS
Sequence in context: A376412 A202489 A213810 * A252145 A249082 A175972
KEYWORD
nonn
AUTHOR
Derek Orr, Sep 22 2014
STATUS
approved