cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-3 of 3 results.

A086066 a(n) = Sum_{d in D(n)} 2^d, where D(n) = set of digits of n in decimal representation.

Original entry on oeis.org

1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 3, 2, 6, 10, 18, 34, 66, 130, 258, 514, 5, 6, 4, 12, 20, 36, 68, 132, 260, 516, 9, 10, 12, 8, 24, 40, 72, 136, 264, 520, 17, 18, 20, 24, 16, 48, 80, 144, 272, 528, 33, 34, 36, 40, 48, 32, 96, 160, 288, 544, 65, 66, 68, 72, 80
Offset: 0

Views

Author

Reinhard Zumkeller, Jul 08 2003

Keywords

Comments

For bitwise logical operations AND and OR:
a(m) = (a(m) AND a(n)) iff D(m) is a subset of D(n),
(a(m) AND a(n)) = 0 iff D(m) and D(n) are disjoint,
a(m) = (a(m) OR a(n)) iff D(n) is a subset of D(m),
a(m) = a(n) iff D(m) = D(n);
A086067(n) = A007088(a(n)).
From Reinhard Zumkeller, Sep 18 2009: (Start)
a(A052382(n)) mod 2 = 0; a(A011540(n)) mod 2 = 1;
for n > 0: a(A000004(n))=1, a(A000042(n))=2, a(A011557(n))=3, a(A002276(n))=4, a(A111066(n))=6, a(A002277(n))=8, a(A002278(n))=16, a(A002279(n))=32, a(A002280(n))=64, a(A002281(n))=128, a(A002282(n))=256, a(A002283(n))=512;
a(n) <= 1023. (End)

Examples

			n=242, D(242) = {2,4}: a(242) = 2^2 + 2^4 = 20.
		

Programs

  • Maple
    A086066 := proc(n) local d: if(n=0)then return 1: fi: d:=convert(convert(n,base,10),set): return add(2^d[j],j=1..nops(d)): end: seq(A086066(n),n=0..64); # Nathaniel Johnston, May 31 2011

A086068 Min{k: A086066(k) = n}.

Original entry on oeis.org

0, 1, 10, 2, 20, 12, 102, 3, 30, 13, 103, 23, 203, 123, 1023, 4, 40, 14, 104, 24, 204, 124, 1024, 34, 304, 134, 1034, 234, 2034, 1234, 10234, 5, 50, 15, 105, 25, 205, 125, 1025, 35, 305, 135, 1035, 235, 2035, 1235, 10235, 45, 405, 145, 1045, 245, 2045
Offset: 1

Views

Author

Reinhard Zumkeller, Jul 08 2003

Keywords

Comments

Sequence is finite with last term a(2^10-1)=a(1023)=1023456789; A086067(1023456789)=1111111111.

Crossrefs

Programs

  • Maple
    A086068 := proc(n) local b,k,s: s:={}: if(n=1)then return 0: fi: b:=convert(n,base,2): for k from 1 to nops(b) do if(b[k] = 1)then s:=s union {k-1}: fi: od: s:=sort(convert(s,list)): if(s[1]=0)then return s[2]*10^(nops(s)-1)+add(s[j]*10^(nops(s)-j),j=3..nops(s)): else return add(s[j]*10^(nops(s)-j),j=1..nops(s)): fi: end: seq(A086068(n),n=1..53); # Nathaniel Johnston, Jun 01 2011

A086084 A086070 in binary.

Original entry on oeis.org

1, 10, 11, 101, 111, 1011, 1101, 1111, 10111, 11011, 11101, 11111, 101111, 110111, 111011, 111101, 111111, 1011111, 1101111, 1110111, 1111011, 1111101, 1111111, 10111111, 11011111, 11101111, 11110111, 11111011, 11111101
Offset: 1

Views

Author

Reinhard Zumkeller, Jul 08 2003

Keywords

Comments

a(n) = A007088(A086070(n)).

Crossrefs

Showing 1-3 of 3 results.