OFFSET
1,1
LINKS
Diana Mecum, Table of n, a(n) for n = 1..131
EXAMPLE
When "n" = 21, the base two concatenated range of integers from 1 to 21 is "1101110010111011110001001101010111100110111101111100001000110010100111010010101". 21 in base two is "10101".
Note that there are two instances of "10101" in the concatenated number when disjoint patterns are considered. There are three pattern matches when overlapping patterns are considered.
MATHEMATICA
f[n_, k_] := StringCount[ ToString@ FromDigits@ Flatten@ IntegerDigits[ Range@n, 2], ToString@ FromDigits@ IntegerDigits[n, 2], Overlaps -> {True, False}[[k]]]; Select[ Range@ 725, f[ #, 1] != f[ #, 2] &] (* Robert G. Wilson v, Aug 30 2008 *)
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Diana L. Mecum, Aug 06 2008
STATUS
approved