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.

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A122229 a(n) = A014486(A122228(n)).

Original entry on oeis.org

0, 2, 12, 56, 228, 920, 3684, 14744, 58980, 235928, 943716, 3774872, 15099492, 60397976, 241591908, 966367640, 3865470564, 15461882264, 61847529060, 247390116248, 989560464996, 3958241859992, 15832967439972
Offset: 0

Views

Author

Antti Karttunen, Sep 14 2006

Keywords

Comments

A simple formula exists, cf. A080675.

Crossrefs

A122230 shows the same sequence in binary. Compare to similar Wolframesque plots given in A080070, A122232, A122235, A122239, A122242, A122245.

A122232 a(n) = A014486(A122231(n)).

Original entry on oeis.org

42, 212, 992, 3876, 15448, 64644, 252056, 989988, 4108676, 16147220, 63393540, 266083460, 1047285272, 4245874244, 16903342544, 67034166420, 274274527940, 1068738181764, 4246566244100, 17369295361736, 67322784388376, 269731897678032
Offset: 1

Views

Author

Antti Karttunen, Sep 14 2006

Keywords

Crossrefs

A122233 shows the same sequence in binary. Compare to similar Wolframesque plots given in A080070, A122229, A122235, A122239, A122242, A122245.

A122235 a(n) = A014486(A122234(n)).

Original entry on oeis.org

44, 216, 968, 3860, 16132, 62064, 247236, 1044612, 4073156, 16161828, 64513624, 253336008, 1046901060, 4267950372, 16347521428, 68075401492, 268150646664, 1086041921700, 4254535157576, 17346201751972, 66879000490408, 276319489325472
Offset: 1

Views

Author

Antti Karttunen, Sep 14 2006

Keywords

Crossrefs

A122236 shows the same sequence in binary. Compare to similar Wolframesque plots given in A080070, A122229, A122232, A122239, A122242, A122245.

A122239 a(n) = A014486(A122238(n)).

Original entry on oeis.org

52, 240, 964, 3972, 15556, 64532, 248288, 988964, 4164356, 15899248, 64719124, 257019652, 1070118936, 4197239188, 16299415152, 65592597568, 259741591312, 1093901323332, 4233842104068, 16616683414632, 70137217092164
Offset: 1

Views

Author

Antti Karttunen, Sep 14 2006

Keywords

Comments

A122240 shows the same sequence in binary.

Crossrefs

Compare to similar Wolframesque plots given in A080070, A122229, A122232, A122235, A122242, A122245.

A122244 Iterates of A122237, starting from 5.

Original entry on oeis.org

5, 21, 55, 183, 512, 1724, 6085, 20899, 66106, 231841, 888275, 3188220
Offset: 1

Views

Author

Antti Karttunen, Sep 14 2006

Keywords

Crossrefs

Programs

A179757 a(n) = A014486(A179756(n)).

Original entry on oeis.org

56, 228, 932, 3736, 15512, 62040, 242264, 969136, 3985840, 15943080, 62096808, 248388496, 1021909904, 4087635248, 15883066672, 63532285248, 261545377088, 1046181434696, 4065904153928, 16263616920064, 66960253254144
Offset: 1

Views

Author

Antti Karttunen, Aug 03 2010

Keywords

Crossrefs

A179777 Position of ones in A179776.

Original entry on oeis.org

1, 2, 6, 10, 15, 17, 22, 25, 31, 33, 34, 35, 39, 41, 42, 43, 47, 49, 50, 51, 55, 57, 62, 64, 65, 71, 79, 80, 84, 89, 92, 94, 99, 101, 103, 108, 110, 111, 115, 119, 124, 126, 127, 128, 132, 134, 135, 136, 140, 142, 144, 149, 151, 156, 160, 164, 165, 166, 167, 168
Offset: 1

Views

Author

Antti Karttunen, Aug 03 2010

Keywords

Comments

This seems to give the positions where "L"'s occur in the central column of A122245 (please zoom into the illustration given here). Conjecture, from a(56)=164 onward, all integers >= 164 present.

Crossrefs

Cf. A179778-A179779, and also A179772, A179832.

A154473 a(n) = A014486(A154472(n)).

Original entry on oeis.org

842, 11090, 13202, 46882, 60994, 231272004, 198873570440, 266349291297936, 64442911458703648, 3667589230123774528, 3336154829743802737792, 17601566387699271821281536, 1023499990310357893964861952
Offset: 0

Views

Author

Antti Karttunen, with terms a(0)-a(100) also independently computed by Wouter Meeussen, with the given Mathematica program, Jan 11 2009

Keywords

Comments

This sequence gives the parenthesis expressions shown at the upper right corner image of the page 103 of NKS, with the left brackets (black squares) converted to 1's and the right brackets (white squares) converted to 0's and then interpreting each such number as a binary number and converted to decimal. A154474 shows the corresponding binary representations. Compare to A080070, A122242, A122245.

Crossrefs

Programs

  • Mathematica
    init=e[e[e][e]][e][e]
    toDeca[ w_ ]:=FromDigits[ ToExpression[ Characters[ ToString[ w ] ]/.{"e"->Sequence[], "["->"1","]"->"0"} ],2 ]
    toDeca /@ NestList[ #/.e[x_ ][y_ ]->x[x[y]]&, init, 100]

A179755 a(n) = A014486(A179754(n)).

Original entry on oeis.org

50, 216, 868, 3492, 13976, 56472, 225880, 897624, 3590576, 14471600, 57886120, 229868968, 919477136, 3706264464, 14825053488, 58832739632, 235330977088, 948740144448, 3794960504136, 15061020431688, 60244082031104
Offset: 1

Views

Author

Antti Karttunen, Aug 03 2010

Keywords

Crossrefs

a(n+1) = A004758(A179757(n)). Cf. also A122242, A122245.

A179417 a(n) is the binary number (shown here in decimal) constructed from quadratic residues of 65537 in range [(n^2)+1,(n+1)^2] in such a way that quadratic residues are mapped to 1-bits, and non-quadratic residues (as well as the multiples of 65537) to 0-bits, with the lower end of range mapped to less significant, and the higher end of range to more significant bits.

Original entry on oeis.org

1, 5, 24, 104, 279, 2001, 4131, 17453, 88826, 362532, 1655660, 6120642, 25376649, 128526482, 301370205, 1756488602, 8046359747, 30854867177, 73845140753, 488906501177, 2106640948770, 6573967883049, 29711211505300
Offset: 0

Views

Author

Antti Karttunen, Jul 27 2010

Keywords

Comments

The binary width of terms are 1, 3, 5, 7, 9, ... i.e., the successive odd numbers, as their partial sums give the squares, 1, 4, 9, 16, ... at which points there certainly is always a quadratic residue, which thus gives the most significant bit for each number.

Examples

			In the range [(2^2)+1, (2+1)^2] (i.e., [5,9]) we have A165471(5)=A165471(6)=A165471(7)=-1 and A165471(8)=A165471(9)=+1, i.e., there are quadratic non-residues at points 5, 6 and 7, and quadratic residues at 8 and 9, so we construct a binary number 11000, which is 24 in decimal, thus a(2)=24.
		

Crossrefs

Cf. A179418.
Compare to similar bit triangle illustrations given in A080070, A122229, A122232, A122235, A122239, A122242, A122245.
Previous Showing 11-20 of 21 results. Next