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 1-6 of 6 results.

A294996 Numbers n such that the largest digit of n^3 is 6.

Original entry on oeis.org

4, 6, 25, 36, 37, 40, 51, 60, 64, 77, 85, 86, 117, 118, 134, 136, 146, 154, 185, 218, 236, 250, 345, 360, 370, 374, 381, 384, 400, 405, 465, 510, 585, 586, 587, 600, 606, 625, 640, 705, 770, 805, 806, 825, 845, 850, 860, 1011, 1021, 1045, 1046, 1081, 1101, 1124, 1136, 1145, 1146, 1170, 1177, 1180
Offset: 1

Views

Author

M. F. Hasler, Nov 13 2017

Keywords

Comments

For any term a(n), all numbers of the form a(n)*10^k, k >= 0, are in this sequence. We could call "primitive" the terms not of this form, i.e., without trailing '0'.
Includes a*10^k+b for k >= 3 and [a,b] in {[11, 1], [5, 4], [4, 5], [6, 5], [5, 6], [11, 10], [1, 11], [10, 11]}, and 8*10^k+8 for k >= 4. - Robert Israel, Jul 22 2019

Examples

			4 is in the sequence because the largest digit of 4^3 = 64 is 6.
		

Crossrefs

Cf. A295021 (the corresponding cubes); A278937, A294664, A294665, A294997 .. A294999 (same for digit 3, ..., 9); A295006 (same for squares).
Cf. A000578 (the cubes).

Programs

  • PARI
    for(n=1,2e3, vecmax(digits(n^3))==6&&print1(n","))

A295025 Cubes whose largest digit is 5.

Original entry on oeis.org

125, 512, 125000, 405224, 512000, 531441, 1225043, 5000211, 5545233, 13312053, 43243551, 54010152, 102503232, 115501303, 125000000, 221445125, 320013504, 400315553, 405224000, 512000000, 531441000, 1204550144, 1225043000, 2053225511, 2253243231, 2543302125
Offset: 1

Views

Author

M. F. Hasler, Nov 12 2017

Keywords

Comments

For any term a(n), all numbers of the form a(n)*10^3k, k >= 0, are in this sequence. Primitive terms, i.e., not of this form (or equivalently: without trailing '0'), are 125, 512, 405224, 531441, 1225043, 5000211, 5545233, 13312053, 43243551, ...

Examples

			512 is in the sequence because it is a cube, 512 = 8^3, and its largest digit is 5.
		

Crossrefs

Cf. A294665 (the corresponding cube roots), A278936 and A294663 (same for digit 3 and 4).
Cf. A000578 (the cubes).

Programs

  • PARI
    for(n=1,2e8, vecmax(digits(n^3))==5&&print1(n^3,","))
    
  • Python
    def ok(cube): return max(str(cube)) == "5"
    print([c for c in (i**3 for i in range(1370)) if ok(c)]) # Michael S. Branicky, Dec 05 2021

Formula

a(n) = A294665(n)^3.

A294664 Numbers n such that the largest digit of n^3 is 4.

Original entry on oeis.org

7, 68, 70, 324, 680, 700, 3240, 6800, 7000, 7618, 31177, 32400, 52308, 68000, 69314, 70000, 76180, 311770, 324000, 353068, 523080, 680000, 693140, 700000, 756658, 761800, 1039247, 2715974, 2732441, 3117700, 3240000, 3511617, 3530680, 4689368, 5230800, 6800000, 6931400, 7000000
Offset: 1

Views

Author

M. F. Hasler, Nov 12 2017

Keywords

Comments

For any term a(n), all numbers of the form a(n)*10^k, k >= 0, are in this sequence. Primitive terms, i.e., not of this form (or equivalently: without trailing '0'), are 7, 68, 324, 7618, 31177, 52308, 69314, 353068, 756658, 1039247, 2715974, 2732441, 3511617, 4689368, 7571814, 12811968, 15904541, ...
All terms have last nonzero digit 1, 4, 7 or 8 and leading digit <= 7. - Robert Israel, Nov 13 2017
The number formed by the first m digits of a term is always less than c*10^m with c = (4/9)^(1/3) = .7631428283688879... - M. F. Hasler, Nov 13 2017

Examples

			7 is in the sequence because the largest digit of 7^3 = 343 is 4.
		

Crossrefs

Cf. A294663 (the corresponding cubes), A278937, A294665, A294996 - A294999 (analog for digits 3, 5, 6 - 9); A277961 (analog for squares).
Cf. A000578 (the cubes).

Programs

  • Maple
    select(n -> max(convert(n^3,base,10))=4, [$1..10^6]); # Robert Israel, Nov 13 2017
  • PARI
    for(n=1,2e8, vecmax(digits(n^3))==4&&print1(n","))

A294999 Numbers n such that the largest digit of n^3 is 9.

Original entry on oeis.org

9, 13, 16, 17, 19, 21, 27, 28, 29, 31, 33, 34, 39, 41, 43, 45, 46, 48, 49, 57, 58, 59, 61, 66, 69, 71, 73, 76, 79, 84, 89, 90, 97, 98, 99, 103, 106, 108, 109, 112, 113, 116, 119, 124, 125, 128, 129, 130, 131, 132, 139, 143, 144, 148, 149, 151, 156, 157, 158, 159, 160, 164, 165, 166, 169
Offset: 1

Views

Author

M. F. Hasler, Nov 13 2017

Keywords

Comments

For any term a(n), all numbers of the form a(n)*10^k, k >= 0, are in this sequence. We could call "primitive" the terms not of this form, i.e., without trailing '0'.

Examples

			13 is in the sequence because the largest digit of 13^3 = 2197 is 9.
		

Crossrefs

Cf. A295024 (the corresponding cubes); A278937, A294664, A294665, A294996, A294997, A294998 (same for digit 3, ..., 8).
Cf. A000578 (the cubes).

Programs

  • Mathematica
    Select[Range[200],Max[IntegerDigits[#^3]]==9&] (* Harvey P. Dale, Jul 08 2018 *)
  • PARI
    for(n=1,200, vecmax(digits(n^3))==9&&print1(n","))

A294997 Numbers n such that the largest digit of n^3 is 7.

Original entry on oeis.org

3, 14, 15, 23, 26, 30, 54, 55, 56, 63, 65, 67, 78, 91, 105, 111, 121, 126, 133, 135, 137, 140, 147, 150, 163, 167, 168, 173, 176, 188, 197, 226, 230, 245, 256, 258, 260, 273, 276, 291, 293, 295, 300, 318, 321, 343, 346, 375, 376, 385, 386, 397, 415, 417, 418, 424, 425, 488, 497
Offset: 1

Views

Author

M. F. Hasler, Nov 13 2017

Keywords

Comments

For any term a(n), all numbers of the form a(n)*10^k, k >= 0, are in this sequence. We could call "primitive" the terms not of this form, i.e., without trailing '0'.

Examples

			3 is in the sequence because the largest digit of 3^3 = 27 is 7.
		

Crossrefs

Cf. A295022 (the corresponding cubes); A278937, A294664, A294665, A294996 .. A294999 (same for digit 3, ..., 9).
Cf. A000578 (the cubes).

Programs

  • Mathematica
    Select[Range[500],Max[IntegerDigits[#^3]]==7&] (* Harvey P. Dale, Sep 10 2019 *)
  • PARI
    for(n=1,2e3, vecmax(digits(n^3))==7&&print1(n","))

A294998 Numbers n such that the largest digit of n^3 is 8.

Original entry on oeis.org

2, 12, 18, 20, 22, 24, 32, 35, 38, 42, 44, 47, 52, 53, 62, 72, 75, 82, 83, 87, 88, 92, 93, 94, 95, 96, 102, 104, 114, 115, 120, 122, 123, 127, 138, 141, 142, 145, 152, 153, 155, 161, 162, 172, 174, 180, 182, 183, 186, 192, 194, 195, 200, 201, 202, 203, 205, 206, 217, 220, 228, 232, 238, 240, 242, 244, 251
Offset: 1

Views

Author

M. F. Hasler, Nov 13 2017

Keywords

Comments

For any term a(n), all numbers of the form a(n)*10^k, k >= 0, are in this sequence. We could call "primitive" the terms not of this form, i.e., without trailing '0'.

Examples

			12 is in the sequence because the largest digit of 12^3 = 1728 is 8.
		

Crossrefs

Cf. A295023 (the corresponding cubes); A278937, A294664, A294665, A294996 .. A294999 (same for digit 3, ..., 9); A295008 (same for squares).
Cf. A000578 (the cubes).

Programs

  • Maple
    filter:= n -> max(convert(n^3,base,10))=8:
    select(filter, [$1..1000]); # Robert Israel, Jul 03 2020
  • Mathematica
    Select[Range[300],Max[IntegerDigits[#^3]]==8&] (* Harvey P. Dale, Aug 21 2019 *)
  • PARI
    for(n=1,500, vecmax(digits(n^3))==8&&print1(n","))
Showing 1-6 of 6 results.