A262094 - OEIS

A262094

Orders m for which the only perfect digital invariants of order m are 0 and 1.

1, 2, 12, 15, 18, 22, 26, 28, 30, 40, 41, 48, 50, 52, 58, 80, 82, 88, 98, 103, 106, 130, 135, 136, 138, 139, 140, 142, 150, 152, 159, 164, 165, 166

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OFFSET

1,2

COMMENTS

a(1), a(2), ... are the indices m for which A255668(m)=2, also A003321(m)=0, also A046761(m)=1.

The values seem to appear in clusters.

LINKS

EXAMPLE

a(3)=12 because there's no solution to x=(x_{12}...x_1x_0)_{10} = x_{12}^{12}+...+x_1^{12}+x_0^{12} except x=0 and x=1.

CROSSREFS

KEYWORD

nonn,base,more

AUTHOR

Don Knuth, Sep 10 2015

STATUS

approved