Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: id:A099902
Displaying 1-1 of 1 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
A099902 Multiplies by 2 and shifts right under the XOR BINOMIAL transform (A099901). +0
5
1, 3, 7, 11, 23, 59, 103, 139, 279, 827, 1895, 2955, 5655, 14395, 24679, 32907, 65815, 197435, 460647, 723851, 1512983, 3881019, 6774887, 9142411, 18219287, 54002491, 123733863, 192940939, 369104407, 939538491, 1610637415, 2147516555 (list; graph; listen)
OFFSET

0,2

COMMENT

Equals the XOR BINOMIAL transform of A099901. Also, equals the main diagonal of the XOR difference triangle A099900, in which the central terms of the rows form the powers of 2.

Bisection of A101624. - Paul Barry (pbarry(AT)wit.ie), May 10 2005

FORMULA

a(n) = SumXOR_{k=0..n} (C(n-k+[k/2], [k/2])mod 2)*2^k for n>=0. a(n) = SumXOR_{i=0..n} (C(n, i)mod 2)*A099901(n-i), where SumXOR is the analogue of summation under the binary XOR operation, and C(i, j)mod 2 = A047999(i, j).

a(n) = Sum_{k=0..n} A047999(n-k+[k/2], [k/2]) * 2^k.

a(n)=sum{k=0..2n, (binomial(k, 2n-k) mod 2)*2^(2n-k)}; a(n)=sum{k=0..n, (binomial(2n-k, k) mod 2)*2^k}; - Paul Barry (pbarry(AT)wit.ie), May 10 2005

PROGRAM

(PARI) {a(n)=local(B); B=0; for(k=0, n, B=bitxor(B, binomial(n-k+k\2, k\2)%2*2^k)); B}

(PARI) a(n)=sum(k=0, n, binomial(n-k+k\2, k\2)%2*2^k)

CROSSREFS

Cf. A099884, A099900, A099901.

Sequence in context: A139253 A116606 A139814 this_sequence A092284 A024459 A001645

Adjacent sequences: A099899 A099900 A099901 this_sequence A099903 A099904 A099905

KEYWORD

eigen,nonn

AUTHOR

Paul D. Hanna (pauldhanna(AT)juno.com), Oct 30 2004

page 1

Search completed in 0.002 seconds

Lookup | Welcome | Find friends | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
More pages | Superseeker | Maintained by N. J. A. Sloane (njas@research.att.com)

Last modified November 21 14:49 EST 2008. Contains 150807 sequences.


AT&T Labs Research