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A367362
Comma transform of the nonnegative integers.
5
1, 12, 23, 34, 45, 56, 67, 78, 89, 91, 1, 11, 21, 31, 41, 51, 61, 71, 81, 92, 2, 12, 22, 32, 42, 52, 62, 72, 82, 93, 3, 13, 23, 33, 43, 53, 63, 73, 83, 94, 4, 14, 24, 34, 44, 54, 64, 74, 84, 95, 5, 15, 25, 35, 45, 55, 65, 75, 85, 96, 6, 16, 26, 36, 46, 56, 66, 76, 86, 97, 7, 17, 27, 37, 47, 57, 67, 77, 87, 98, 8, 18
OFFSET
0,2
COMMENTS
See A367360 for further information.
LINKS
Eric Angelini, Michael S. Branicky, Giovanni Resta, N. J. A. Sloane, and David W. Wilson, The Comma Sequence: A Simple Sequence With Bizarre Properties, arXiv:2401.14346, Youtube
FORMULA
a(n) = 10 * A010879(n) + A000030(n+1). - Alois P. Heinz, Nov 22 2023
MAPLE
a:= n-> parse(cat(""||n[-1], ""||(n+1)[1])):
seq(a(n), n=0..99); # Alois P. Heinz, Nov 22 2023
MATHEMATICA
FromDigits /@ Partition[Rest@ Flatten[{First[#], Last[#]} & /@ IntegerDigits[Range[0, 120]]], 2, 2] (* Michael De Vlieger, Nov 22 2023 *)
PROG
(Python)
from itertools import count, islice, pairwise
def S(): yield from (str(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(), 82))) # Michael S. Branicky, Nov 22 2023
(Python)
def A367362(n): return (n%10)*10+int(str(n+1)[0]) # Chai Wah Wu, Dec 22 2023
CROSSREFS
KEYWORD
nonn,base
AUTHOR
N. J. A. Sloane, Nov 22 2023
STATUS
approved