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A187186
Parse the infinite string 0123456701234567012345670... into distinct phrases 0, 1, 2, 3, 4, 5, 6, 7, 01, 23, 45, 67, 012, 34, ...; a(n) = length of n-th phrase.
2
1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 3, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 4, 4, 5, 4, 4, 5, 4, 4, 5, 4, 4, 5, 5, 5, 5, 5, 6, 6, 6, 6, 7, 6, 6, 6, 6, 7, 7, 7, 7, 7, 7, 7, 8, 9, 8, 9, 8, 9, 8, 9, 8, 9, 8, 9, 8, 9, 8, 9, 10, 10, 10, 10, 11, 10, 10, 10, 10, 11, 11, 11, 11, 11, 11, 11, 12, 12, 13, 12, 12, 13, 12, 12, 13, 12, 12, 13, 13, 13, 13, 13, 14, 14, 14, 14, 15, 14, 14, 14, 14, 15, 15, 15, 15, 15, 15, 15
OFFSET
1,9
COMMENTS
See A187180 for details.
LINKS
Index entries for linear recurrences with constant coefficients, signature (1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, -1).
FORMULA
After the initial block of eight 1's, the sequence is quasi-periodic with period 64, increasing by 8 after each block.
a(n) ~ n/8. - Charles R Greathouse IV, May 30 2026
PROG
(PARI) a(n)=if(n>7, (n+[8, -1, 6, -3, 4, -5, 2, -7, 0, 7, 6, 5, 4, 11, 2, 1, 0, -1, 6, 5, 4, 3, 2, 1, 0, 7, 6, 13, 4, 3, 10, 1, 0, 7, -2, -3, 4, 3, 2, 1, 0, 7, 6, 5, 4, 11, 2, 1, 0, -1, 6, 5, 4, 3, 2, 1, 0, 7, 14, 5, 12, 3, 10, 1][n%64+1])/8, 1) \\ Charles R Greathouse IV, May 30 2026
CROSSREFS
See A187180-A187188 for alphabets of size 2 through 10.
Sequence in context: A067131 A094915 A217619 * A259651 A253719 A081147
KEYWORD
nonn,easy
AUTHOR
N. J. A. Sloane, Mar 06 2011
STATUS
approved