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A367361
Comma transform of powers of 2.
3
12, 24, 48, 81, 63, 26, 41, 82, 65, 21, 42, 84, 68, 21, 43, 86, 61, 22, 45, 81, 62, 24, 48, 81, 63, 26, 41, 82, 65, 21, 42, 84, 68, 21, 43, 86, 61, 22, 45, 81, 62, 24, 48, 81, 63, 27, 41, 82, 65, 21, 42, 84, 69, 21, 43, 87, 61, 22, 45, 81, 62, 24, 49, 81, 63, 27, 41, 82, 65, 21, 42, 84, 69, 21, 43, 87, 61, 23, 46, 81
OFFSET
0,1
COMMENTS
See A367360 for further information.
LINKS
FORMULA
a(n) = 10 * A000689(n) + A008952(n+1). - Alois P. Heinz, Nov 22 2023
MATHEMATICA
FromDigits /@ Partition[Rest@ Flatten[{First[#], Last[#]} & /@ IntegerDigits[2^Range[0, 120]]], 2, 2] (* Michael De Vlieger, Nov 22 2023 *)
PROG
(Python)
from itertools import count, islice, pairwise
def S(): yield from (str(2**i) for i in count(0))
def agen(): yield from (int(t[-1]+u[0]) for t, u in pairwise(S()))
print(list(islice(agen(), 80))) # Michael S. Branicky, Nov 22 2023
(Python)
def A367361(n): return (60, 20, 40, 80)[n&3]+int(str(1<<n+1)[0]) if n else 12 # Chai Wah Wu, Dec 22 2023
CROSSREFS
KEYWORD
nonn,base
AUTHOR
N. J. A. Sloane, Nov 22 2023
STATUS
approved