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.

A291631 Numbers k such that 6 is the smallest decimal digit of k^2.

Original entry on oeis.org

26, 83, 264, 313, 824, 836, 883, 887, 937, 3114, 8167, 8813, 8887, 8937, 9417, 9833, 25824, 26264, 29614, 29626, 89324, 89437, 93637, 94863, 98336, 260167, 262617, 314113, 817863, 817924, 818333, 818474, 823887, 828667, 835386, 875614, 931117, 936417, 937383
Offset: 1

Views

Author

Colin Barker, Aug 28 2017

Keywords

Comments

9949370777987917 is the smallest number k such that the smallest decimal digit of k^2 is 7. - Chai Wah Wu, Sep 08 2017

Examples

			26 is in the sequence because 26^2 = 676, the smallest decimal digit of which is 6.

Links

Crossrefs

Cf. A291625, A291626, A291627, A291628, A291629, A291630.

Programs

  • Mathematica
    Select[Range[10^6], Min[IntegerDigits[#^2]]==6 &] (* Vincenzo Librandi, Sep 09 2017 *)
  • PARI
    select(k->vecmin(digits(k^2))==6, vector(1000000, k, k))

A291626 Numbers k such that 1 is the smallest decimal digit of k^2.

Original entry on oeis.org

1, 4, 9, 11, 12, 13, 14, 19, 21, 29, 31, 34, 35, 36, 37, 38, 39, 41, 42, 43, 44, 46, 54, 56, 59, 61, 69, 72, 79, 81, 89, 91, 96, 106, 107, 108, 109, 111, 112, 113, 114, 115, 116, 117, 118, 119, 121, 122, 123, 124, 125, 126, 127, 128, 129, 131, 132, 133, 134
Offset: 1

Views

Author

Colin Barker, Aug 28 2017

Keywords

Examples

			29 is in the sequence because 29^2 = 841, the smallest decimal digit of which is 1.

Links

Crossrefs

Cf. A291625, A291627, A291628, A291629, A291630, A291631.

Programs

  • Mathematica
    Select[Range[200],Min[IntegerDigits[#^2]]==1&] (* Harvey P. Dale, Sep 07 2019 *)
  • PARI
    select(k->vecmin(digits(k^2))==1, vector(1000, k, k))
  • Python
    A291626_list = [k for k in range(1,10**6) if min(str(k**2)) == '1'] # Chai Wah Wu, Aug 28 2017

A291629 Numbers k such that 4 is the smallest decimal digit of k^2.

Original entry on oeis.org

2, 7, 8, 22, 28, 67, 74, 88, 92, 93, 212, 214, 216, 234, 238, 242, 258, 262, 293, 308, 667, 676, 678, 683, 684, 692, 707, 738, 758, 772, 817, 822, 828, 863, 864, 866, 886, 888, 892, 893, 926, 938, 972, 974, 978, 2113, 2114, 2116, 2133, 2137, 2158, 2163, 2167
Offset: 1

Views

Author

Colin Barker, Aug 28 2017

Keywords

Comments

First digit can't be 1, 4 or 5; last digit can't be 0, 1 or 9. - Robert Israel, Mar 25 2020

Examples

			28 is in the sequence because 28^2 = 784, the smallest decimal digit of which is 4.

Links

Crossrefs

Cf. A291625, A291626, A291627, A291628, A291630, A291631.

Programs

  • Maple
    filter:= n -> min(convert(n^2,base,10))=4:
select(filter, [$1..10000]); # Robert Israel, Mar 25 2020
  • Mathematica
    Select[Range[2500],Min[IntegerDigits[#^2]]==4&] (* Harvey P. Dale, Aug 03 2019 *)
  • PARI
    select(k->vecmin(digits(k^2))==4, vector(3000, k, k))

A291630 Numbers k such that 5 is the smallest decimal digit of k^2.

Original entry on oeis.org

24, 76, 87, 236, 314, 316, 766, 816, 834, 2366, 2383, 2387, 2424, 2563, 2626, 2976, 7613, 7666, 8117, 8184, 8234, 8286, 8366, 8716, 8814, 9266, 9316, 9363, 9474, 9786, 9837, 23634, 23784, 23866, 23874, 24474, 25663, 25684, 26076, 26187, 26374, 26417, 27687
Offset: 1

Views

Author

Colin Barker, Aug 28 2017

Keywords

Examples

			87 is in the sequence because 87^2 = 7569, the smallest decimal digit of which is 5.

Links

Crossrefs

Cf. A291625, A291626, A291627, A291628, A291629, A291631.

Programs

  • Mathematica
    Select[Range[30000],Min[IntegerDigits[#^2]]==5&] (* Harvey P. Dale, Nov 03 2023 *)
  • PARI
    select(k->vecmin(digits(k^2))==5, vector(30000, k, k))
  • Python
    A291630_list = [k for k in range(1,10**6) if min(str(k**2)) == '5'] # Chai Wah Wu, Aug 28 2017

A291625 Numbers k such that 0 is the smallest decimal digit of k^2.

Original entry on oeis.org

10, 20, 30, 32, 33, 40, 45, 47, 48, 49, 50, 51, 52, 53, 55, 60, 64, 70, 71, 78, 80, 84, 90, 95, 97, 98, 99, 100, 101, 102, 103, 104, 105, 110, 120, 130, 138, 140, 142, 143, 144, 145, 147, 148, 149, 150, 151, 152, 153, 155, 160, 170, 174, 175, 176, 179, 180
Offset: 1

Views

Author

Colin Barker, Aug 28 2017

Keywords

Examples

			47 is in the sequence because 47^2 = 2209, the smallest decimal digit of which is 0.

Crossrefs

Cf. A291626, A291627, A291628, A291629, A291630, A291631.

Programs

  • PARI
    select(k->vecmin(digits(k^2))==0, vector(1000, k, k))
  • Python
    A291625_list = [k for k in range(1,10**6) if '0' in str(k**2)] # Chai Wah Wu, Aug 28 2017

A291627 Numbers k such that 2 is the smallest decimal digit of k^2.

Original entry on oeis.org

5, 15, 16, 17, 18, 23, 25, 27, 57, 65, 68, 73, 75, 77, 82, 85, 156, 157, 158, 162, 163, 164, 165, 166, 167, 168, 172, 173, 185, 193, 206, 207, 208, 215, 218, 222, 223, 232, 233, 235, 273, 275, 277, 278, 282, 287, 288, 292, 307, 315, 472, 473, 474, 475, 476
Offset: 1

Views

Author

Colin Barker, Aug 28 2017

Keywords

Examples

			278 is in the sequence because 278^2 = 77284, the smallest decimal digit of which is 2.

Crossrefs

Cf. A291625, A291626, A291628, A291629, A291630, A291631.

Programs

  • PARI
    select(k->vecmin(digits(k^2))==2, vector(1000, k, k))
Showing 1-6 of 6 results.

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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