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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A079933 Greedy powers of (1/sqrt(3)): sum_{n=1..inf} (1/sqrt(3))^a(n) = 1.

Original entry on oeis.org

1, 2, 5, 7, 11, 12, 19, 22, 27, 33, 37, 39, 42, 44, 53, 54, 60, 62, 68, 69, 75, 77, 78, 83, 86, 87, 91, 94, 97, 100, 101, 105, 106, 110, 113, 115, 116, 120, 121, 125, 129, 131, 132, 137, 141, 144, 148, 149, 152, 155, 157, 166, 171, 173, 178, 179, 184, 186, 189, 191
Offset: 1

Views

Author

Ulrich Schimke (ulrschimke(AT)aol.com), Jan 16 2003

Keywords

Comments

The n-th greedy power of x, when 0.5 < x < 1, is the smallest integer exponent a(n) that does not cause the power series sum_{k=1..n} x^a(k) to exceed unity.

Examples

			a(3)=5 since (1/sqrt(3)) + (1/sqrt(3))^2 + (1/sqrt(3))^5 < 1 and (1/sqrt(3)) + (1/sqrt(3))^2 + (1/sqrt(3))^4 > 1; the power 4 makes the sum > 1, so 5 is the 3rd greedy power of (1/sqrt(3)).
		

Crossrefs

Formula

a(n)=sum_{k=1..n}floor(g_k) where g_1=1, g_{n+1}=log_x(x^frac(g_n) - x) (n>0) at x=(1/sqrt(3)) and frac(y) = y - floor(y).

A073536 Breaking indices for A058842 (i.e., n such that A058842(n) is not equal to 3*A058842 (n-1) ).

Original entry on oeis.org

3, 9, 12, 15, 17, 27, 34, 39, 46, 49, 52, 54, 66, 70, 73, 81, 84, 90, 95, 102, 106, 110, 116, 119, 124, 132, 140, 143, 149, 153, 158, 161, 165, 171, 177, 180, 183, 186, 189, 194, 198, 209, 215, 221, 224, 226, 233, 235, 241, 244, 248, 251, 255, 259, 262, 272
Offset: 1

Views

Author

Benoit Cloitre, Aug 27 2002

Keywords

Crossrefs

Cf. A058842.

Formula

It seems that a(n) = 5*n +O(log(n)) and that a(n)=5*n for infinitely many values of n.
It appears that a(n)=A077468(n+1). - Benoit Cloitre, Jun 04 2004

A079931 Greedy powers of (1/sqrt(Pi)): Sum_{n>=1} (1/sqrt(Pi))^a(n) = 1.

Original entry on oeis.org

1, 2, 4, 8, 9, 16, 20, 22, 23, 32, 33, 36, 39, 42, 43, 46, 47, 50, 51, 55, 59, 60, 63, 69, 74, 77, 80, 82, 87, 92, 94, 97, 100, 102, 105, 107, 111, 113, 114, 117, 119, 122, 126, 128, 129, 134, 141, 142, 146, 147, 150, 151, 154, 157, 160, 162, 165, 167, 168, 171, 175
Offset: 1

Views

Author

Ulrich Schimke (ulrschimke(AT)aol.com), Jan 16 2003

Keywords

Comments

The n-th greedy power of x, when 0.5 < x < 1, is the smallest integer exponent a(n) that does not cause the power series Sum_{k=1..n} x^a(k) to exceed unity.

Examples

			a(3)=4 since (1/sqrt(Pi)) + (1/sqrt(Pi))^2 + (1/sqrt(Pi))^4 < 1 and (1/sqrt(Pi)) + (1/sqrt(Pi))^2 + (1/sqrt(Pi))^3 > 1; the power 3 makes the sum > 1, so 4 is the 3rd greedy power of (1/sqrt(Pi)).
		

Crossrefs

Formula

a(n) = Sum_{k=1..n} floor(g_k) where g_1=1, g_{n+1} = log_x(x^frac(g_n) - x) (n > 0) at x = (1/sqrt(Pi)) and frac(y) = y - floor(y).

A079932 Greedy powers of (1/sqrt(2)): sum_{n=1..inf} (1/sqrt(2))^a(n) = 1.

Original entry on oeis.org

1, 4, 10, 13, 22, 27, 32, 36, 40, 49, 54, 62, 66, 71, 80, 91, 97, 102, 109, 114, 120, 124, 127, 138, 146, 149, 159, 165, 169, 180, 184, 187, 194, 202, 208, 219, 224, 231, 235, 248, 258, 263, 266, 274, 281, 287, 294, 300, 304, 308, 316, 323, 329, 337, 343, 350
Offset: 1

Views

Author

Ulrich Schimke (ulrschimke(AT)aol.com), Jan 16 2003

Keywords

Comments

The n-th greedy power of x, when 0.5 < x < 1, is the smallest integer exponent a(n) that does not cause the power series sum_{k=1..n} x^a(k) to exceed unity.

Examples

			a(3)=10 since (1/sqrt(2)) + (1/sqrt(2))^4 + (1/sqrt(2))^10 < 1 and (1/sqrt(2)) + (1/sqrt(2))^4 + (1/sqrt(2))^9 > 1; the power 9 makes the sum > 1, so 10 is the 3rd greedy power of (1/sqrt(2)).
		

Crossrefs

Formula

a(n)=sum_{k=1..n}floor(g_k) where g_1=1, g_{n+1}=log_x(x^frac(g_n) - x) (n>0) at x=(1/sqrt(2)) and frac(y) = y - floor(y).

A080056 Greedy powers of (2/Pi): Sum_{n=1..inf} (2/Pi)^a(n) = 1.

Original entry on oeis.org

1, 3, 5, 16, 22, 24, 28, 34, 37, 43, 45, 49, 51, 54, 57, 59, 65, 68, 70, 74, 80, 88, 94, 97, 100, 103, 108, 111, 113, 116, 122, 127, 129, 132, 137, 141, 143, 148, 151, 156, 161, 164, 166, 172, 174, 177, 184, 189, 202, 204, 208, 213, 216, 219, 225, 227, 238, 247
Offset: 1

Views

Author

Benoit Cloitre and Paul D. Hanna, Jan 23 2003

Keywords

Comments

The n-th greedy power of x, when 0.5 < x < 1, is the smallest integer exponent a(n) that does not cause the power series Sum_{k=1..n} x^a(k) to exceed unity. A heuristic argument suggests that the limit of a(n)/n is m - Sum_{n=m..inf} log(1 + x^n)/log(x) = 4.2164448079..., where x=(2/Pi) and m=floor(log(1-x)/log(x))=2.
See A077468 for Mathematica program by Robert G. Wilson v.

Examples

			a(3)=5 since (2/Pi) +(2/Pi)^3 +(2/Pi)^5 < 1 and (2/Pi) +(2/Pi)^3 +(2/Pi)^k > 1 for 3<k<5.
		

Crossrefs

Formula

a(n) = Sum_{k=1..n} floor(g_k) where g_1=1, g_{n+1}=log_x(x^frac(g_n) - x) (n>0) at x=(2/Pi) and frac(y) = y - floor(y).

A080057 Greedy powers of exp(-gamma): Sum_{n>=1} exp(-gamma)^a(n) = 1, where exp(-gamma) = exp(-.57721566490153286...) = .561459483566885169...

Original entry on oeis.org

1, 2, 4, 7, 9, 13, 15, 17, 20, 21, 23, 27, 29, 34, 35, 38, 40, 42, 43, 46, 48, 49, 51, 54, 57, 58, 61, 64, 65, 68, 73, 74, 80, 83, 85, 87, 89, 98, 100, 101, 104, 105, 107, 110, 113, 116, 117, 120, 122, 123, 126, 128, 132, 136, 139, 142, 149, 152, 156, 157, 160, 161, 163
Offset: 1

Views

Author

Benoit Cloitre and Paul D. Hanna, Jan 23 2003

Keywords

Comments

The n-th greedy power of x, when 0.5 < x < 1, is the smallest integer exponent a(n) that does not cause the power series Sum_{k=1..n} x^a(k) to exceed unity. A heuristic argument suggests that the limit of a(n)/n is m - Sum_{n>=m} log(1 + x^n)/log(x) = 2.909795625992782..., where x=exp(-gamma) and m=floor(log(1-x)/log(x))=1.
See A077468 for Mathematica program by Robert G. Wilson v.

Examples

			a(3)=4 since exp(-gamma) + exp(-gamma)^2 + exp(-gamma)^4 < 1 and exp(-gamma) + exp(-gamma)^2 + exp(-gamma)^k > 1 for 2<k<4.
		

Crossrefs

Formula

a(n) = Sum_{k=1..n} floor(g_k) where g_1=1, g_{n+1}=log_x(x^frac(g_n) - x) (n>0) at x=(exp(-Gamma)) and frac(y) = y - floor(y).

A080059 Greedy powers of (1/zeta(3)): Sum_{n>=1} (1/zeta(3))^a(n) = 1, where 1/zeta(3) = .83190737258070746868...

Original entry on oeis.org

1, 10, 26, 38, 54, 64, 80, 98, 115, 126, 136, 147, 158, 171, 181, 196, 206, 226, 243, 257, 267, 279, 293, 306, 324, 334, 355, 365, 378, 388, 398, 410, 432, 442, 455, 468, 491, 501, 519, 534, 545, 560, 572, 582, 593, 610, 628, 638, 650, 663, 672, 691, 704, 715
Offset: 1

Views

Author

Benoit Cloitre and Paul D. Hanna, Jan 23 2003

Keywords

Comments

The n-th greedy power of x, when 0.5 < x < 1, is the smallest integer exponent a(n) that does not cause the power series Sum_{k=1..n} x^a(k) to exceed unity. A heuristic argument suggests that the limit of a(n)/n is m - Sum_{n>=m} log(1 + x^n)/log(x) = 14.874449248373..., where x=(1/zeta(3)) and m=floor(log(1-x)/log(x))=9.
See A077468 for Mathematica program by Robert G. Wilson v.

Examples

			a(3)=26 since (1/zeta(3)) +(1/zeta(3))^10 +(1/zeta(3))^26 < 1 and (1/zeta(3)) +(1/zeta(3))^10 +(1/zeta(3))^k > 1 for 10<k<26.
		

Crossrefs

Formula

a(n) = Sum_{k=1..n} floor(g_k) where g_1=1, g_{n+1}=log_x(x^frac(g_n) - x) (n>0) at x=(1/zeta(3)) and frac(y) = y - floor(y).

A079450 a(n) = 2^(n-1)*u(n) where u(1)=1 and u(n) = frac(3/2*u(n-1)) + 1.

Original entry on oeis.org

1, 3, 5, 15, 29, 55, 101, 175, 269, 807, 1397, 2143, 6429, 11095, 16901, 50703, 86573, 259719, 517013, 1026751, 2031677, 3997879, 7799333, 15009391, 28250957, 51198439, 86486453, 259459359, 509942621, 992956951, 1905129029, 3567903439
Offset: 1

Views

Author

Benoit Cloitre, Jan 13 2003

Keywords

Programs

  • Mathematica
    u[1]:= 1; u[n_]:= u[n]= FractionalPart[3*u[n-1]/2] +1; a[n_]:= 2^(n-1)* u[n]; Table[a[n], {n, 1, 40}] (* G. C. Greubel, Jan 18 2019 *)

Formula

a(n+1)<=3*a(n). Conjecture : a(n+1)=3*a(n) if and only if n is a greedy power of (2/3) (i.e. n is in A077468)

A080055 Greedy powers of log(2): Sum_{n>=1} (log(2))^a(n) = 1.

Original entry on oeis.org

1, 4, 8, 11, 15, 20, 23, 30, 38, 43, 49, 54, 60, 65, 72, 78, 85, 90, 93, 100, 104, 108, 111, 115, 118, 122, 128, 132, 140, 144, 147, 152, 156, 159, 171, 174, 178, 181, 188, 191, 196, 203, 206, 210, 213, 232, 244, 248, 256, 260, 265, 269, 272, 276, 285, 289, 293
Offset: 1

Views

Author

Benoit Cloitre and Paul D. Hanna, Jan 23 2003

Keywords

Comments

The n-th greedy power of x, when 0.5 < x < 1, is the smallest integer exponent a(n) that does not cause the power series Sum_{k=1..n} x^a(k) to exceed unity. A heuristic argument suggests that the limit of a(n)/n is m - Sum_{n>=m} log(1 + x^n)/log(x) = 5.7114827587..., where x = log(2) and m = floor(log(1-x)/log(x))=3.
See A077468 for Mathematica program by Robert G. Wilson v.

Examples

			a(3)=8 since (log(2)) + (log(2))^4 + (log(2))^8 < 1 and (log(2)) + (log(2))^4 + (log(2))^k > 1 for 4 < k < 8.
		

Crossrefs

Formula

a(n) = Sum_{k=1..n} floor(g_k) where g_1=1, g_{n+1} = log_x(x^frac(g_n) - x) (n>0) at x=log(2) and frac(y) = y - floor(y).

A080058 Greedy powers of (1/zeta(2)): Sum_{n>=1} (1/zeta(2))^a(n) = 1, where 1/zeta(2) = 6/Pi^2 = .607927101854...

Original entry on oeis.org

1, 2, 8, 12, 14, 16, 25, 39, 42, 44, 46, 49, 51, 53, 59, 70, 73, 78, 81, 83, 85, 86, 101, 103, 105, 116, 118, 119, 126, 130, 135, 137, 139, 142, 144, 147, 148, 158, 161, 163, 170, 171, 178, 181, 186, 188, 190, 192, 194, 195, 204, 207, 209, 212, 216, 219, 224, 229
Offset: 1

Views

Author

Benoit Cloitre and Paul D. Hanna, Jan 23 2003

Keywords

Comments

The n-th greedy power of x, when 0.5 < x < 1, is the smallest integer exponent a(n) that does not cause the power series Sum_{k=1..n} x^a(k) to exceed unity. A heuristic argument suggests that the limit of a(n)/n is m - Sum_{n>=m} log(1 + x^n)/log(x) = 3.66565771136..., where x=(1/zeta(2)) and m=floor(log(1-x)/log(x))=1.
See A077468 for Mathematica program by Robert G. Wilson v.

Examples

			a(3)=8 since (1/zeta(2)) +(1/zeta(2))^2 +(1/zeta(2))^8 < 1 and (1/zeta(2)) +(1/zeta(2))^2 +(1/zeta(2))^k > 1 for 2<k<8.
		

Crossrefs

Formula

a(n) = Sum_{k=1..n} floor(g_k) where g_1=1, g_{n+1}=log_x(x^frac(g_n) - x) (n>0) at x=(1/zeta(2)) and frac(y) = y - floor(y).
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