|
Search: id:A065761
|
|
|
| A065761 |
|
Concatenation of increasing number of alternating digits in base 2, starting with 0. |
|
+0
3
|
|
| 0, 3, 24, 399, 12768, 817215, 104603520, 26778501375, 13710592704000, 14039646928897023, 28753196910381103104, 117773094544920998318079, 964797190511992818221703168, 15807237169348490333744384720895
(list; graph; listen)
|
|
|
OFFSET
|
1,2
|
|
|
COMMENT
|
The first 5 terms in base 2 are 0, (0)11, (0)11000, (0)110001111, (0)11000111100000.
|
|
LINKS
|
Harry J. Smith, Table of n, a(n) for n=1,...,50
|
|
FORMULA
|
a(1) = 0; a(n+1) = append n+1 0's or 1's (alternately) to a(n).
|
|
EXAMPLE
|
a(5) = 12768 is formed by appending 0 five times (00000) to a(4) in base 2: (0)11000111100000.
|
|
PROGRAM
|
(PARI) baseI(x, b)= { local(d, e=0, f=1); while (x>0, d=x-10*(x\10); x\=10; e+=d*f; f*=b); return(e) } { c=1; for (n=1, 50, if (n==1, a=0; b=0, c=c*10 + 1; if (n%2, d=0, d=c); b=b*10^n + d; a=baseI(b, 2)); write("b065761.txt", n, " ", a) ) } [From Harry J. Smith (hjsmithh(AT)sbcglobal.net), Oct 30 2009]
|
|
CROSSREFS
|
Cf. A065760, A065447.
Sequence in context: A153389 A010791 A145169 this_sequence A002832 A166736 A109055
Adjacent sequences: A065758 A065759 A065760 this_sequence A065762 A065763 A065764
|
|
KEYWORD
|
base,easy,nonn
|
|
AUTHOR
|
Lior Manor (lior.manor(AT)gmail.com) Nov 18 2001
|
|
|
Search completed in 0.002 seconds
|
