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 63 results. Next

A296425 Decimal expansion of ratio-sum for A296245; see Comments.

Original entry on oeis.org

1, 4, 9, 7, 6, 3, 2, 7, 1, 4, 4, 8, 5, 6, 3, 0, 4, 1, 2, 4, 1, 1, 6, 8, 9, 6, 3, 5, 6, 2, 6, 9, 8, 7, 9, 3, 6, 1, 3, 5, 1, 0, 5, 0, 4, 8, 2, 1, 7, 4, 9, 2, 0, 3, 2, 2, 3, 6, 7, 0, 3, 3, 5, 7, 8, 3, 0, 6, 8, 4, 9, 2, 4, 3, 3, 2, 4, 0, 5, 8, 2, 6, 9, 4, 7, 2
Offset: 2

Views

Author

Clark Kimberling, Dec 14 2017

Keywords

Comments

Suppose that A = (a(n)), for n >= 0, is a sequence, and g is a real number such that a(n)/a(n-1) -> g. The ratio-sum for A is |a(1)/a(0) - g| + |a(2)/a(1) - g| + ..., assuming that this series converges. For A = A296245, we have g = (1 + sqrt(5))/2, the golden ratio (A001622). See A296425-A296434 for related ratio-sums and A296452-A296461 for related limiting power-ratios.

Examples

			14.9763271448563041241168963...
		

Crossrefs

Programs

  • Mathematica
    a[0] = 1; a[1] = 2; b[0] = 3; b[1] = 4; b[2] = 5;
    a[n_] := a[n] = a[n - 1] + a[n - 2] + b[n]^2;
    j = 1; While[j < 13, k = a[j] - j - 1;
    While[k < a[j + 1] - j + 1, b[k] = j + k + 2; k++]; j++];
    Table[a[n], {n, 0, k}]; (* A296245 *)
    g = GoldenRatio; s = N[Sum[- g + a[n]/a[n - 1], {n, 1, 1000}], 200]
    Take[RealDigits[s, 10][[1]], 100]  (* A296425 *)

A296452 Decimal expansion of limiting power-ratio for A296245; see Comments.

Original entry on oeis.org

3, 5, 9, 2, 9, 5, 4, 9, 2, 5, 5, 5, 8, 3, 1, 8, 4, 0, 9, 0, 2, 1, 6, 6, 6, 8, 7, 8, 3, 5, 1, 2, 1, 9, 1, 3, 2, 0, 7, 1, 5, 1, 8, 3, 9, 7, 5, 7, 9, 0, 8, 5, 6, 0, 7, 0, 8, 3, 0, 3, 1, 7, 9, 1, 0, 5, 2, 3, 9, 2, 8, 0, 5, 5, 2, 9, 5, 3, 9, 2, 1, 7, 7, 5, 4, 6
Offset: 2

Views

Author

Clark Kimberling, Dec 15 2017

Keywords

Comments

Suppose that A = {a(n)}, for n >= 0, is a sequence, and g is a real number such that a(n)/a(n-1) -> g. The limiting power-ratio for A is the limit as n->oo of a(n)/g^n, assuming that this limit exists. For A = A296245 we have g = (1 + sqrt(5))/2, the golden ratio (A001622). See A296425-A296434 for related ratio-sums and A296452-A296461 for related limiting power-ratios.

Examples

			Limiting power-ratio = 35.92954925558318409021666878351219132071...
		

Crossrefs

Programs

  • Mathematica
    a[0] = 1; a[1] = 2; b[0] = 3; b[1] = 4; b[2] = 5;
    a[n_] := a[n] = a[n - 1] + a[n - 2] + b[n]^2;
    j = 1; While[j < 12, k = a[j] - j - 1;
    While[k < a[j + 1] - j + 1, b[k] = j + k + 2; k++]; j++];
    Table[a[n], {n, 0, 15}]  (* A296245 *)
    z = 2000; g = GoldenRatio; h = Table[N[a[n]/g^n, z], {n, 0, z}];
    StringJoin[StringTake[ToString[h[[z]]], 41], "..."]
    Take[RealDigits[Last[h], 10][[1]], 120] (* A296452 *)

A296284 Solution of the complementary equation a(n) = a(n-1) + a(n-2) + n*b(n-2), where a(0) = 1, a(1) = 2, b(0) = 3, and (a(n)) and (b(n)) are increasing complementary sequences.

Original entry on oeis.org

1, 2, 9, 23, 52, 105, 199, 360, 639, 1098, 1857, 3098, 5123, 8416, 13763, 22434, 36485, 59242, 96087, 155728, 252255, 408487, 661292, 1070377, 1732317, 2803394, 4536465, 7340669, 11878002, 19219599, 31098591, 50319244, 81418955, 131739387, 213159600
Offset: 0

Views

Author

Clark Kimberling, Dec 13 2017

Keywords

Comments

The increasing complementary sequences a() and b() are uniquely determined by the titular equation and initial values. a(n)/a(n-1) -> (1 + sqrt(5))/2 = golden ratio (A001622). See A296245 for a guide to related sequences.

Examples

			a(0) = 1, a(1) = 2, b(0) = 3, b(1) = 4, b(2) = 5
a(2) = a(0) + a(1) + 2*b(0) = 9
Complement: (b(n)) = (3, 4, 5, 6, 7, 8, 10, 11, 12, 13, 14, 15, 16, ...)
		

Crossrefs

Programs

  • Mathematica
    a[0] = 1; a[1] = 2; b[0] = 3;
    a[n_] := a[n] = a[n - 1] + a[n - 2] + n*b[n-2];
    j = 1; While[j < 10, k = a[j] - j - 1;
     While[k < a[j + 1] - j + 1, b[k] = j + k + 2; k++]; j++];
    Table[a[n], {n, 0, k}]; (* A296284 *)
    Table[b[n], {n, 0, 20}]    (* complement *)

A294170 Solution of the complementary equation a(n) = a(n-1) + a(n-2) + b(n) + 2*n, where a(0) = 1, a(1) = 2, b(0) = 3, b(1) = 4, b(2) = 5, and (a(n)) and (b(n)) are increasing complementary sequences.

Original entry on oeis.org

1, 2, 12, 26, 53, 97, 171, 292, 490, 813, 1337, 2187, 3564, 5794, 9404, 15247, 24703, 40005, 64766, 104832, 169662, 274561, 444294, 718929, 1163300, 1882309, 3045692, 4928087, 7973868, 12902047, 20876010, 33778155, 54654266, 88432525, 143086898, 231519533
Offset: 0

Views

Author

Clark Kimberling, Feb 10 2018

Keywords

Comments

The increasing complementary sequences a() and b() are uniquely determined by the titular equation and initial values. a(n)/a(n-1) -> (1 + sqrt(5))/2 = golden ratio (A001622). See A296245 for a guide to related sequences.

Examples

			a(0) = 1, a(1) = 2, b(0) = 3, b(1) = 4, b(2) = 5
a(2) = a(0) + a(1) + b(2) + 4 = 12
Complement: (b(n)) = (3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 14, 15, 16, ...)
		

Crossrefs

Programs

  • Mathematica
    a[0] = 1; a[1] = 2; b[0] = 3; b[1] = 4; b[2] = 5;
    a[n_] := a[n] = a[n - 1] + a[n - 2] + b[n] + 2 n;
    j = 1; While[j < 16, k = a[j] - j - 1;
     While[k < a[j + 1] - j + 1, b[k] = j + k + 2; k++]; j++];
    Table[a[n], {n, 0, k}];  (* A294170 *)

A296251 Solution of the complementary equation a(n) = a(n-1) + a(n-2) + b(n-1)^2, where a(0) = 1, a(1) = 2, b(0) = 3, b(1) = 4, and (a(n)) and (b(n)) are increasing complementary sequences.

Original entry on oeis.org

1, 2, 19, 46, 101, 196, 361, 638, 1099, 1858, 3101, 5128, 8425, 13778, 22459, 36526, 59309, 96235, 155985, 252704, 409218, 662498, 1072341, 1735515, 2808585, 4544884, 7354310, 11900094, 19255365, 31156483, 50412937, 81570576, 131984738, 213556610, 345542717
Offset: 0

Views

Author

Clark Kimberling, Dec 10 2017

Keywords

Comments

The increasing complementary sequences a() and b() are uniquely determined by the titular equation and initial values. a(n)/a(n-1) -> (1 + sqrt(5))/2 = golden ratio (A001622). See A296245 for a guide to related sequences.

Examples

			a(0) = 1, a(1) = 2, b(0) = 3, b(1) = 4;
a(2) = a(0) + a(1) + b(1)^2 = 19;
Complement: (b(n)) = (3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 20, ...)
		

Crossrefs

Programs

  • Mathematica
    a[0] = 1; a[1] = 2; b[0] = 3; b[1] = 4;
    a[n_] := a[n] = a[n - 1] + a[n - 2] + b[n-1]^2;
    j = 1; While[j < 6 , k = a[j] - j - 1;
    While[k < a[j + 1] - j + 1, b[k] = j + k + 2; k++]; j++];
    Table[a[n], {n, 0, k}]   (* A296251 *)
    Table[b[n], {n, 0, 20}]  (* complement *)

Formula

a(n) = H + R, where H = f(n-1)*a(0) + f(n)*a(1) and R = f(n-1)*b(1)^2 + f(n-2)*b(2)^2 + ... + f(2)*b(n-2)^2 + f(1)*b(n-1)^2, where f(n) = A000045(n), the n-th Fibonacci number.

A296257 Solution of the complementary equation a(n) = a(n-1) + a(n-2) + b(n-2)^2, where a(0) = 1, a(1) = 2, b(0) = 3, and (a(n)) and (b(n)) are increasing complementary sequences.

Original entry on oeis.org

1, 2, 12, 30, 67, 133, 249, 446, 776, 1322, 2219, 3710, 6125, 10060, 16441, 26790, 43555, 70706, 114661, 185808, 300953, 487290, 788819, 1276734, 2066229, 3343692, 5410705, 8755238, 14166904, 22923166, 37091159, 60015481, 97107865, 157124642, 254233876
Offset: 0

Views

Author

Clark Kimberling, Dec 11 2017

Keywords

Comments

The increasing complementary sequences a() and b() are uniquely determined by the titular equation and initial values. a(n)/a(n-1) -> (1 + sqrt(5))/2 = golden ratio (A001622). See A296245 for a guide to related sequences.

Examples

			a(0) = 1, a(1) = 2, b(0) = 3;
a(2) = a(0) + a(1) + b(0)^2 = 12;
Complement: (b(n)) = (3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 14, ...)
		

Crossrefs

Programs

  • Mathematica
    a[0] = 1; a[1] = 2; b[0] = 3;
    a[n_] := a[n] = a[n - 1] + a[n - 2] + b[n-2]^2;
    j = 1; While[j < 6 , k = a[j] - j - 1;
    While[k < a[j + 1] - j + 1, b[k] = j + k + 2; k++]; j++];
    Table[a[n], {n, 0, k}]     (* A296257 *)
    Table[b[n], {n, 0, 20}]  (* complement *)

Formula

a(n) = H + R, where H = f(n-1)*a(0) + f(n)*a(1) and R = f(n-1)*b(0)^2 + f(n-2)*b(1)^2 + ... + f(2)*b(n-3)^2 + f(1)*b(n-2)^2, where f(n) = A000045(n), the n-th Fibonacci number.

A296266 Solution of the complementary equation a(n) = a(n-1) + a(n-2) + b(n-2)*b(n), where a(0) = 1, a(1) = 2, b(0) = 3, b(1) = 4, b(2) = 5, and (a(n)) and (b(n)) are increasing complementary sequences.

Original entry on oeis.org

1, 2, 18, 44, 97, 189, 349, 618, 1066, 1804, 3013, 4985, 8193, 13402, 21850, 35556, 57746, 93701, 151887, 246071, 398486, 645132, 1044242, 1690049, 2735019, 4425851, 7161710, 11588460, 18751130, 30340613, 49092831, 79434599, 128528654, 207964548, 336494570
Offset: 0

Views

Author

Clark Kimberling, Dec 12 2017

Keywords

Comments

The increasing complementary sequences a() and b() are uniquely determined by the titular equation and initial values. a(n)/a(n-1) -> (1 + sqrt(5))/2 = golden ratio (A001622). See A296245 for a guide to related sequences.

Examples

			a(0) = 1, a(1) = 2, b(0) = 3, b(1) = 1, b(2) = 4, b(3) = 5;
a(2) = a(0) + a(1) + b(0)*b(2) = 18;
Complement: (b(n)) = (3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 19, ...)
		

Crossrefs

Programs

  • Mathematica
    a[0] = 1; a[1] = 2; b[0] = 3; b[1] = 4; b[2] = 5;
    a[n_] := a[n] = a[n - 1] + a[n - 2] + b[n - 2] b[n];
    j = 1; While[j < 10, k = a[j] - j - 1;
    While[k < a[j + 1] - j + 1, b[k] = j + k + 2; k++]; j++];
    Table[a[n], {n, 0, k}];  (* A296266 *)
    Table[b[n], {n, 0, 20}]  (* complement *)

A296272 Solution of the complementary equation a(n) = a(n-1) + a(n-2) + b(n-1)*b(n), where a(0) = 1, a(1) = 2, b(0) = 3, b(1) = 4, b(2) = 5, and (a(n)) and (b(n)) are increasing complementary sequences.

Original entry on oeis.org

1, 2, 23, 55, 120, 231, 423, 744, 1277, 2153, 3586, 5921, 9717, 15878, 25867, 42051, 68260, 110691, 179371, 290524, 470423, 761547, 1232620, 1994869, 3228245, 5223926, 8453041, 13677897, 22131930, 35810883, 57943935, 93756008, 151701203, 245458543, 397161152
Offset: 0

Views

Author

Clark Kimberling, Dec 12 2017

Keywords

Comments

The increasing complementary sequences a() and b() are uniquely determined by the titular equation and initial values. a(n)/a(n-1) -> (1 + sqrt(5))/2 = golden ratio (A001622). See A296245 for a guide to related sequences.

Examples

			a(0) = 1, a(1) = 2, b(0) = 3, b(1) = 4, b(2) = 5;
a(2) = a(0) + a(1) + b(1)*b(2) = 23;
Complement: (b(n)) = (3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, ...)
		

Crossrefs

Programs

  • Mathematica
    a[0] = 1; a[1] = 2; b[0] = 3; b[1] = 4; b[2] = 5;
    a[n_] := a[n] = a[n - 1] + a[n - 2] + b[n - 1] b[n];
    j = 1; While[j < 10, k = a[j] - j - 1;
    While[k < a[j + 1] - j + 1, b[k] = j + k + 2; k++]; j++];
    Table[a[n], {n, 0, k}];  (* A296272 *)
    Table[b[n], {n, 0, 20}]  (* complement *)

A296278 Solution of the complementary equation a(n) = a(n-1) + a(n-2) + b(n-2)*b(n-1)*b(n), where a(0) = 1, a(1) = 2, b(0) = 3, b(1) = 4, b(2) = 5, and (a(n)) and (b(n)) are increasing complementary sequences.

Original entry on oeis.org

1, 2, 63, 185, 458, 979, 1941, 3640, 6571, 11531, 19818, 33533, 56081, 92974, 153135, 251005, 409954, 667799, 1085733, 1762772, 2859131, 4634047, 7506978, 12156625, 19681153, 31857434, 51560511, 83442305, 135029786, 218501851, 353564373, 572102128, 925705771
Offset: 0

Views

Author

Clark Kimberling, Dec 13 2017

Keywords

Comments

The increasing complementary sequences a() and b() are uniquely determined by the titular equation and initial values. a(n)/a(n-1) -> (1 + sqrt(5))/2 = golden ratio (A001622). See A296245 for a guide to related sequences.

Examples

			a(0) = 1, a(1) = 2, b(0) = 3, b(1) = 4, b(2) = 5
a(2) = a(0) + a(1) + b(0)*b(1)*b(2) = 63
Complement: (b(n)) = (3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, ...)
		

Crossrefs

Programs

  • Mathematica
    a[0] = 1; a[1] = 2; b[0] = 3; b[1] = 4; b[2] = 5;
    a[n_] := a[n] = a[n - 1] + a[n - 2] + b[n-2] b[n - 1] b[n];
    j = 1; While[j < 10, k = a[j] - j - 1;
     While[k < a[j + 1] - j + 1, b[k] = j + k + 2; k++]; j++];
    Table[a[n], {n, 0, k}]; (* A296278 *)
    Table[b[n], {n, 0, 20}]    (* complement *)

A296288 Solution of the complementary equation a(n) = a(n-1) + a(n-2) + n*b(n-1), where a(0) = 1, a(1) = 2, b(0) = 3, b(1) = 4, and (a(n)) and (b(n)) are increasing complementary sequences.

Original entry on oeis.org

1, 2, 11, 28, 63, 126, 237, 426, 743, 1277, 2150, 3581, 5911, 9700, 15849, 25819, 41972, 68131, 110481, 179030, 289971, 469505, 760026, 1230129, 1990803, 3221657, 5213240, 8435734, 13649870, 22086561, 35737451, 57825097, 93563700, 151390018, 244955010
Offset: 0

Views

Author

Clark Kimberling, Dec 14 2017

Keywords

Comments

The increasing complementary sequences a() and b() are uniquely determined by the titular equation and initial values. a(n)/a(n-1) -> (1 + sqrt(5))/2 = golden ratio (A001622). See A296245 for a guide to related sequences.

Examples

			a(0) = 1, a(1) = 2, b(0) = 1, b(1) = 3, b(2) = 4
a(2) = a(0) + a(1) + 2*b(0) = 11
Complement: (b(n)) = (3, 4, 5, 6, 7, 8, 9, 10, 12, 13, 14, 15, ...)
		

Crossrefs

Programs

  • Mathematica
    a[0] = 1; a[1] = 2; b[0] = 3; b[1] = 4;
    a[n_] := a[n] = a[n - 1] + a[n - 2] + n*b[n-1];
    j = 1; While[j < 10, k = a[j] - j - 1;
     While[k < a[j + 1] - j + 1, b[k] = j + k + 2; k++]; j++];
    Table[a[n], {n, 0, k}]; (* A296288 *)
    Table[b[n], {n, 0, 20}]    (* complement *)
Showing 1-10 of 63 results. Next