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 1-3 of 3 results.

A385700 Numbers such that when the leftmost digit is moved to the unit's place the result is divisible by 4.

Original entry on oeis.org

0, 4, 8, 21, 23, 25, 27, 29, 40, 42, 44, 46, 48, 61, 63, 65, 67, 69, 80, 82, 84, 86, 88, 201, 203, 205, 207, 209, 211, 213, 215, 217, 219, 221, 223, 225, 227, 229, 231, 233, 235, 237, 239, 241, 243, 245, 247, 249, 251, 253, 255, 257, 259, 261, 263, 265, 267, 269
Offset: 1

Views

Author

Stefano Spezia, Jul 07 2025

Keywords

Examples

			263 is a term since 632 = 158*4 is divisible by 4.
		

Crossrefs

Similar sequences for k=1..9: A001477, A273892, A008585, this sequence, A217398, A385701, A385702, A385703, A008591.

Programs

  • Mathematica
    Select[Range[0,270],Divisible[FromDigits[RotateLeft[IntegerDigits[#]]],4] &]
  • PARI
    isok(k) = if (k==0, return(1)); my(d=digits(k), v = vector(#d-1, i, d[i+1])); v = concat(v, d[1]); fromdigits(v) % 4 == 0; \\ Michel Marcus, Jul 08 2025
    
  • Python
    def ok(n): return int((s:=str(n))[1:]+s[0])%4 == 0
    print([k for k in range(270) if ok(k)]) # Michael S. Branicky, Jul 08 2025

A385701 Numbers such that when the leftmost digit is moved to the unit's place the result is divisible by 6.

Original entry on oeis.org

0, 6, 21, 24, 27, 42, 45, 48, 60, 63, 66, 69, 81, 84, 87, 201, 204, 207, 210, 213, 216, 219, 222, 225, 228, 231, 234, 237, 240, 243, 246, 249, 252, 255, 258, 261, 264, 267, 270, 273, 276, 279, 282, 285, 288, 291, 294, 297, 402, 405, 408, 411, 414, 417, 420, 423, 426, 429
Offset: 1

Views

Author

Stefano Spezia, Jul 07 2025

Keywords

Examples

			426 is a term since 264 = 44*6 is divisible by 6.
		

Crossrefs

Similar sequences for k=1..9: A001477, A273892, A008585, A385700, A217398, this sequence, A385702, A385703, A008591.

Programs

  • Mathematica
    Select[Range[0,430],Divisible[FromDigits[RotateLeft[IntegerDigits[#]]],6] &]
  • PARI
    isok(k) = if (k==0, return(1)); my(d=digits(k), v = vector(#d-1, i, d[i+1])); v = concat(v, d[1]); fromdigits(v) % 6 == 0; \\ Michel Marcus, Jul 08 2025
    
  • Python
    def ok(n): return int((s:=str(n))[1:]+s[0])%6 == 0
    print([k for k in range(430) if ok(k)]) # Michael S. Branicky, Jul 08 2025

A385703 Numbers such that when the leftmost digit is moved to the unit's place the result is divisible by 8.

Original entry on oeis.org

0, 8, 23, 27, 42, 46, 61, 65, 69, 80, 84, 88, 203, 207, 211, 215, 219, 223, 227, 231, 235, 239, 243, 247, 251, 255, 259, 263, 267, 271, 275, 279, 283, 287, 291, 295, 299, 402, 406, 410, 414, 418, 422, 426, 430, 434, 438, 442, 446, 450, 454, 458, 462, 466, 470, 474
Offset: 1

Views

Author

Stefano Spezia, Jul 07 2025

Keywords

Examples

			458 is a term since 584 = 73*8 is divisible by 8.
		

Crossrefs

Similar sequences for k=1..9: A001477, A273892, A008585, A385700, A217398, A385701, A385702, this sequence, A008591.

Programs

  • Mathematica
    Select[Range[0,475],Divisible[FromDigits[RotateLeft[IntegerDigits[#]]],8] &]
  • PARI
    isok(k) = if (k==0, return(1)); my(d=digits(k), v = vector(#d-1, i, d[i+1])); v = concat(v, d[1]); fromdigits(v) % 8 == 0; \\ Michel Marcus, Jul 08 2025
    
  • Python
    def ok(n): return int((s:=str(n))[1:]+s[0])%8 == 0
    print([k for k in range(500) if ok(k)]) # Michael S. Branicky, Jul 08 2025
Showing 1-3 of 3 results.