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A193431
Put the natural numbers together without spaces and read them three at a time advancing one space each time.
5
123, 234, 345, 456, 567, 678, 789, 891, 910, 101, 11, 111, 112, 121, 213, 131, 314, 141, 415, 151, 516, 161, 617, 171, 718, 181, 819, 192, 920, 202, 21, 212, 122, 222, 223, 232, 324, 242, 425, 252, 526, 262, 627, 272, 728, 282, 829, 293, 930, 303, 31, 313
OFFSET
1,1
LINKS
FORMULA
a(n) = 10 * (10 * A007376(n) + A007376(n+1)) + A007376(n+2).
MATHEMATICA
Module[{nn=50, d}, d=Flatten[IntegerDigits/@Range[nn]]; FromDigits/@ Partition[ d, 3, 1]] (* Harvey P. Dale, Nov 16 2021 *)
PROG
(Haskell)
a193431 n = a193431_list !! (n-1)
a193431_list = f a007376_list where
f (x:xs'@(x':x'':xs)) = 10*(10*x + x') + x'' : f xs'
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Reinhard Zumkeller, Jul 28 2011
STATUS
approved