A020667 -id:A020667 - cp's OEIS frontend

A020666 a(n)^n is the least n-th power containing every digit.

1023456789, 32043, 2326, 763, 309, 159, 56, 104, 49, 36, 25, 15, 25, 17, 17, 15, 16, 7, 5, 6, 6, 5, 11, 9, 14, 5, 5, 5, 5, 9, 5, 8, 11, 4, 4, 6, 5, 7, 3, 5, 4, 4, 6, 4, 3, 6, 3, 3, 4, 4, 5, 4, 3, 6, 4, 4, 3, 4, 4, 3, 3, 3, 3, 3, 3, 4, 3, 2, 3, 2, 3, 3, 3, 3, 4, 3, 3, 3, 2, 3, 4, 2, 3, 2, 3, 3, 2, 2, 2

Offset: 1

David W. Wilson

It is extremely probable that a(n) = 2 for all n >= 169.

Seiichi Manyama, Table of n, a(n) for n = 1..10000

Cf. A020667, A112388, A137214.

def a(n):
    if n == 1: return 1023456789
    an = 2
    while not(len(set(str(an**n))) == 10): an += 1
    return an
print([a(n) for n in range(1, 90)]) # Michael S. Branicky, Jul 04 2021

A217535 Least number having in its decimal representation each digit n times.

Original entry on oeis.org

1023456789, 10012233445566778899, 100011222333444555666777888999, 1000011122223333444455556666777788889999, 10000011112222233333444445555566666777778888899999, 100000011111222222333333444444555555666666777777888888999999

Offset: 1

M. F. Hasler, Oct 05 2012

Alois P. Heinz, Table of n, a(n) for n = 1..100

Cf. A050278, A051018, A049363, A074205, A154566, A204047, A020666, A020667, A061604, A180489.

A subsequence of A171102.

a:= n-> parse(cat(1,0$n,1$(n-1),seq(i$n, i=2..9))):
seq(a(n), n=1..10);  # Alois P. Heinz, Jun 25 2017

A217535(n)=sum(d=1,9,10^(n-(d==1))\9*d*10^(n*(9-d)))+10^(10*n-1)

a(n) ~ 10^(10n-1). See PARI code for an exact formula.

cp's OEIS Frontend

A020666 a(n)^n is the least n-th power containing every digit.

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