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 1-2 of 2 results.

A190682 Squares whose squares contain every digit at least once.

Original entry on oeis.org

582169, 588289, 1136356, 1183744, 1454436, 1700416, 2030625, 2424249, 2436721, 2669956, 2732409, 2930944, 3024121, 3175524, 3305124, 3381921, 3481956, 3526884, 3900625, 4129024, 4182025, 4223025, 4553956, 4804864, 4981824
Offset: 1

Views

Author

Bruno Berselli, May 17 2011

Keywords

Comments

Squares in A054038.

Examples

			a(2) = A054038(2225) = 588289 = 767^2.
		

Programs

  • Magma
    [ n^2: n in [0..2232] | Seqset(Intseq(n^4)) eq {0..9} ];

Formula

a(n) = A121321(n)^2.

A345875 Numbers whose fourth powers are zeroless pandigital.

Original entry on oeis.org

608, 809, 897, 924, 1166, 1241, 1458, 1459, 1506, 1547, 1718, 1729, 1832, 1932, 1977, 1982, 2112, 2162, 2179, 2188, 2211, 2279, 2283, 2291, 2296, 2336, 2337, 2408, 2427, 2541, 2592, 2594, 2613, 2634, 2684, 2689, 2704, 2764, 2776, 2779, 2854, 2941, 2984, 2988, 3009
Offset: 1

Views

Author

Tanya Khovanova, Jun 27 2021

Keywords

Comments

Zeroless pandigital means that it contains all the digits 1 through 9, but doesn't contain a zero.

Examples

			608^4 = 136651472896. Thus, 608 belongs to this sequence.
		

Crossrefs

Cf. A071519 (for squares), A124628 (for cubes).
Subsequence of A121321 (4th power is pandigital).

Programs

  • Maple
    q:= n-> is({convert(n^4, base, 10)[]}={$1..9}):
    select(q, [$1..3000])[];  # Alois P. Heinz, Jun 29 2021
  • Mathematica
    Select[Range[8000], Union[IntegerDigits[#^4]] == {1, 2, 3, 4, 5, 6, 7, 8, 9} &]
  • PARI
    isok(k) = my(d=digits(k^4)); vecmin(d) && (#Set(d) == 9); \\ Michel Marcus, Jun 30 2021
  • Python
    def ok(n): return set(str(n**4)) == set("123456789")
    print(list(filter(ok, range(3000)))) # Michael S. Branicky, Jun 27 2021
    
Showing 1-2 of 2 results.