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 1-10 of 11 results. Next

A257803 Positions of odd numbers in A233271, the infinite trunk of inverted binary beanstalk.

Original entry on oeis.org

1, 4, 7, 9, 12, 17, 18, 21, 23, 24, 25, 27, 30, 34, 35, 38, 41, 42, 49, 52, 53, 54, 55, 57, 60, 64, 65, 68, 70, 73, 74, 75, 76, 77, 81, 82, 83, 90, 93, 95, 96, 103, 106, 107, 108, 109, 111, 114, 118, 119, 122, 127, 128, 131, 132, 134, 136, 137, 138, 139, 140, 145, 147, 148, 149, 150, 151, 155, 156, 157, 164, 167, 168, 171
Offset: 1

Views

Author

Antti Karttunen, May 12 2015

Keywords

Crossrefs

Complement: A257804.

Formula

Other identities:
For all n >= 1, A257807(a(n)) = n. [A257807 works as a left inverse for this injective function.]

A257804 Positions of even numbers in A233271, the infinite trunk of inverted binary beanstalk.

Original entry on oeis.org

0, 2, 3, 5, 6, 8, 10, 11, 13, 14, 15, 16, 19, 20, 22, 26, 28, 29, 31, 32, 33, 36, 37, 39, 40, 43, 44, 45, 46, 47, 48, 50, 51, 56, 58, 59, 61, 62, 63, 66, 67, 69, 71, 72, 78, 79, 80, 84, 85, 86, 87, 88, 89, 91, 92, 94, 97, 98, 99, 100, 101, 102, 104, 105, 110, 112, 113, 115, 116, 117, 120, 121, 123, 124, 125, 126, 129, 130
Offset: 0

Views

Author

Antti Karttunen, May 12 2015

Keywords

Comments

We start indexing of this sequence from 0, because a(0) = 0 is a special case, which can be conveniently ignored by considering only the terms from a(1) onward.

Crossrefs

Complement: A257803.

Formula

Other identities. For all n >= 0:
A257808(a(n)) = n. [A257808 works as a left inverse for this injective function.]

A257807 a(n) = number of odd numbers in range 0 .. n of A233271, the infinite trunk of inverted binary beanstalk.

Original entry on oeis.org

0, 1, 1, 1, 2, 2, 2, 3, 3, 4, 4, 4, 5, 5, 5, 5, 5, 6, 7, 7, 7, 8, 8, 9, 10, 11, 11, 12, 12, 12, 13, 13, 13, 13, 14, 15, 15, 15, 16, 16, 16, 17, 18, 18, 18, 18, 18, 18, 18, 19, 19, 19, 20, 21, 22, 23, 23, 24, 24, 24, 25, 25, 25, 25, 26, 27, 27, 27, 28, 28, 29, 29, 29, 30, 31, 32, 33, 34, 34, 34, 34, 35, 36, 37, 37, 37, 37, 37, 37, 37, 38
Offset: 0

Views

Author

Antti Karttunen, May 12 2015

Keywords

Comments

a(0) = 0; and for n >= 1: a(n) = the largest number k such that A257803(k) <= n.

Crossrefs

Partial sums of A257800.

Formula

a(0) = 0; for n >= 1, a(n) = A257800(n) + a(n-1).
Other identities:
For all n >= 0, a(n) = A257808(n) - A257806(n).
For all n >= 1, a(A257803(n)) = n. [This sequence works as a left inverse of injection A257803.]

A257808 a(n) = number of nonzero even numbers in range 0 .. n of A233271, the infinite trunk of inverted binary beanstalk.

Original entry on oeis.org

0, 0, 1, 2, 2, 3, 4, 4, 5, 5, 6, 7, 7, 8, 9, 10, 11, 11, 11, 12, 13, 13, 14, 14, 14, 14, 15, 15, 16, 17, 17, 18, 19, 20, 20, 20, 21, 22, 22, 23, 24, 24, 24, 25, 26, 27, 28, 29, 30, 30, 31, 32, 32, 32, 32, 32, 33, 33, 34, 35, 35, 36, 37, 38, 38, 38, 39, 40, 40, 41, 41, 42, 43, 43, 43, 43, 43, 43, 44, 45, 46, 46, 46, 46, 47, 48, 49, 50, 51
Offset: 0

Views

Author

Antti Karttunen, May 12 2015

Keywords

Comments

a(n) = the largest number k such that A257804(k) <= n.

Crossrefs

Formula

a(0) = 0; for n >= 1, a(n) = (1-A257800(n)) + a(n-1).
Other identities. For all n >= 0:
a(n) = A257806(n) + A257807(n).
a(A257804(n)) = n. [This sequence works as a left inverse for injection A257804.]

A260430 Involution of natural numbers: a(1) = 1, a(A257803(1+n)) = A257804(a(n)), a(A257804(n)) = A257803(1+a(n)), where A257803 and A257804 give the positions of odd and even terms in A233271, the infinite trunk of inverted binary beanstalk.

Original entry on oeis.org

1, 4, 12, 2, 30, 7, 6, 74, 19, 21, 18, 3, 172, 52, 54, 49, 48, 11, 9, 383, 10, 128, 125, 32, 36, 132, 31, 119, 118, 5, 27, 24, 812, 314, 89, 25, 283, 92, 275, 76, 86, 85, 83, 290, 75, 267, 266, 17, 16, 68, 60, 14, 724, 15, 227, 1675, 219, 659, 207, 51, 64, 599, 216, 61, 232, 583, 174, 50, 204, 210, 201, 193, 208, 8, 45, 40, 1574, 612, 173, 569, 595, 159, 43
Offset: 1

Views

Author

Antti Karttunen, Jul 27 2015

Keywords

Crossrefs

Cf. also A233271, A257806.
Related permutations: A260431 - A260434.

Formula

a(1) = 1; for n > 1, if A257800(n) = 0 [when n is one of the terms of A257804] a(n) = A257803(1+a(A257808(n))), otherwise [when n is one of the terms of A257803] a(n) = A257804(a(A257807(n)-1)).

A260431 Permutation of natural numbers: a(1) = 1, a(A257804(n)) = 2*a(n), a(A257803(1+n)) = 1 + 2*a(n), where A257804 and A257803 give the positions of even and odd terms in A233271, the infinite trunk of inverted binary beanstalk.

Original entry on oeis.org

1, 2, 4, 3, 8, 6, 5, 16, 9, 12, 10, 7, 32, 18, 24, 20, 17, 13, 14, 64, 11, 36, 33, 19, 25, 48, 21, 40, 34, 15, 26, 28, 128, 65, 37, 22, 72, 49, 66, 38, 41, 35, 50, 96, 42, 80, 68, 30, 27, 52, 56, 29, 129, 23, 73, 256, 67, 130, 74, 39, 44, 144, 98, 51, 97, 132, 76, 43, 82, 81, 70, 100, 69, 31, 53, 57, 257, 192, 84, 160, 131, 75, 45, 136, 60, 54
Offset: 1

Views

Author

Antti Karttunen, Jul 27 2015

Keywords

Crossrefs

Inverse: A260432.
Related permutations: A260433, A260430, A054429.
Cf. also A257806.

Formula

a(1) = 1; for n > 1, if A257800(n) = 0 [when n is one of the terms of A257804] a(n) = 2*a(A257808(n)), otherwise [when n is one of the terms of A257803] a(n) = 1 + 2*a(A257807(n)-1).
As a composition of other permutations:
a(n) = A054429(A260433(n)).
a(n) = A260433(A260430(n)).

A260432 Permutation of natural numbers: a(1) = 1, a(2n) = A257804(a(n)), a(2n+1) = A257803(1+a(n)), where A257804 and A257803 give the positions of even and odd terms in A233271, the infinite trunk of inverted binary beanstalk.

Original entry on oeis.org

1, 2, 4, 3, 7, 6, 12, 5, 9, 11, 21, 10, 18, 19, 30, 8, 17, 14, 24, 16, 27, 36, 54, 15, 25, 31, 49, 32, 52, 48, 74, 13, 23, 29, 42, 22, 35, 40, 60, 28, 41, 45, 68, 61, 83, 92, 132, 26, 38, 43, 64, 50, 75, 86, 119, 51, 76, 89, 128, 85, 118, 125, 172, 20, 34, 39, 57, 47, 73, 71, 106, 37, 55, 59, 82, 67, 96, 101, 140, 46, 70, 69
Offset: 1

Views

Author

Antti Karttunen, Jul 27 2015

Keywords

Comments

This sequence can be represented as a binary tree. Each left hand child is produced as A257804(n), and each right hand child as A257803(1+n), when the parent contains n:
|
...................1...................
2 4
3......../ \........7 6......../ \........12
/ \ / \ / \ / \
/ \ / \ / \ / \
/ \ / \ / \ / \
5 9 11 21 10 18 19 30
8 17 14 24 16 27 36 54 15 25 31 49 32 52 48 74
etc.

Crossrefs

Inverse: A260431.
Related permutations: A260434, A260430, A054429.
Cf. also A233271, A257806.

Formula

a(1) = 1, a(2n) = A257804(a(n)), a(2n+1) = A257803(1+a(n)).
As a composition of other permutations:
a(n) = A260434(A054429(n)).
a(n) = A260430(A260434(n)).

A260434 Permutation of natural numbers: a(1) = 1, a(2n) = A257803(1+a(n)), a(2n+1) = A257804(a(n)), where A257803 and A257804 give the positions of odd and even terms in A233271, the infinite trunk of inverted binary beanstalk.

Original entry on oeis.org

1, 4, 2, 12, 6, 7, 3, 30, 19, 18, 10, 21, 11, 9, 5, 74, 48, 52, 32, 49, 31, 25, 15, 54, 36, 27, 16, 24, 14, 17, 8, 172, 125, 118, 85, 128, 89, 76, 51, 119, 86, 75, 50, 64, 43, 38, 26, 132, 92, 83, 61, 68, 45, 41, 28, 60, 40, 35, 22, 42, 29, 23, 13, 383, 314, 275, 219, 266, 208, 201, 152, 283, 227, 207, 159, 174, 129, 127, 88
Offset: 1

Views

Author

Antti Karttunen, Jul 27 2015

Keywords

Comments

This sequence can be represented as a binary tree. Each left hand child is produced as A257803(1+n), and each right hand child as A257804(n), when the parent contains n:
|
...................1...................
4 2
12......../ \........6 7......../ \........3
/ \ / \ / \ / \
/ \ / \ / \ / \
/ \ / \ / \ / \
30 19 18 10 21 11 9 5
74 48 52 32 49 31 25 15 54 36 27 16 24 14 17 8
etc.
Note how this is a mirror image of the tree shown in A260432.

Crossrefs

Inverse: A260433.
Related permutations: A260432, A260430, A054429.
Cf. also A233271, A257806.

Formula

a(1) = 1, a(2n) = A257803(1+a(n)), a(2n+1) = A257804(a(n)).
As a composition of other permutations:
a(n) = A260432(A054429(n)).
a(n) = A260430(A260432(n)).

A257805 Partial sums of A257259: a(0) = 1; for n >= 1, a(n) = A257259(n) + a(n-1).

Original entry on oeis.org

1, 0, 0, -1, -2, -5, -6, -12, -20, -30, -37, -41, -39, -37, -51, -141, -459, -1355, -3521, -8212, -17510, -34685, -64692, -114953, -196617, -326254, -527227, -828432, -1254932, -1800115, -2361626, -2613748, -1777205, 1765725, 11078200, 31587185, 72445272, 148564309, 283768148, 516004565, 906713910, 1559424960, 2660917133, 4581930804, 8140743021, 15311144248, 31111188060, 68512065476
Offset: 0

Views

Author

Antti Karttunen, May 13 2015

Keywords

Crossrefs

Formula

a(0) = 1; for n >= 1, a(n) = A257259(n) + A257805(n-1).
Other identities. For all n >= 0:
a(n) = -A257806(A218600(n+1)).

A260433 Permutation of natural numbers: a(1) = 1, a(A257803(1+n)) = 2*a(n), a(A257804(n)) = 1 + 2*a(n), where A257803 and A257804 give the positions of odd and even terms in A233271, the infinite trunk of inverted binary beanstalk.

Original entry on oeis.org

1, 3, 7, 2, 15, 5, 6, 31, 14, 11, 13, 4, 63, 29, 23, 27, 30, 10, 9, 127, 12, 59, 62, 28, 22, 47, 26, 55, 61, 8, 21, 19, 255, 126, 58, 25, 119, 46, 125, 57, 54, 60, 45, 95, 53, 111, 123, 17, 20, 43, 39, 18, 254, 24, 118, 511, 124, 253, 117, 56, 51, 239, 93, 44, 94, 251, 115, 52, 109, 110, 121, 91, 122, 16, 42, 38, 510, 191, 107, 223, 252, 116, 50, 247, 35, 41
Offset: 1

Views

Author

Antti Karttunen, Jul 27 2015

Keywords

Crossrefs

Inverse: A260434.
Related permutations: A260431, A260430, A054429.
Cf. also A233271, A257806.

Formula

a(1) = 1; for n > 1, if A257800(n) = 0 [when n is one of the terms of A257804] a(n) = 1 + 2*a(A257808(n)), otherwise [when n is one of the terms of A257803] a(n) = 2*a(A257807(n)-1).
As a composition of other permutations:
a(n) = A054429(A260431(n)).
a(n) = A260431(A260430(n)).
Showing 1-10 of 11 results. Next