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A362343
Sequence that alternately doubles and squares the previous number; a(0) = 1.
1
1, 2, 4, 8, 64, 128, 16384, 32768, 1073741824, 2147483648, 4611686018427387904, 9223372036854775808, 85070591730234615865843651857942052864, 170141183460469231731687303715884105728, 28948022309329048855892746252171976963317496166410141009864396001978282409984
OFFSET
0,2
FORMULA
a(0) = 1; a(n) = a(n-1)*2 if n is odd, otherwise a(n) = a(n-1)^2.
a(n) = 2^A075427(n-1), for n>=1.
PROG
(Python)
def A362343(n): return 1<<((1<<(n>>1)+1)-1 if n&1 else (1<<(n>>1)+1)-2) # Chai Wah Wu, Apr 23 2023
CROSSREFS
Cf. A075427.
Subsequence of A000079.
Sequence in context: A263451 A339951 A069027 * A065549 A067507 A320898
KEYWORD
nonn,easy
AUTHOR
Christopher Roat, Apr 17 2023
STATUS
approved