A152182 The sequence is a lattice filling using the exponential "E" constant digits base ten.

1, 21, 371, 8090, 102125, 1061609, 12108836, 198150335, 1929504527

Offset: 0

Author

Roger L. Bagula, Nov 28 2008, extended Nov 30 2008, Nov 30 2008

Keywords

• nonn
• uned
• base

Crossrefs

Cf. A001113.

Programs

Mathematica

f[ 0 ] := 1; f[ n_Integer /; n > 0 ] := Module[ {i, cnt, m, p}, i = 0; cnt = 0; m = Table[ 0, {10^n} ]; p = Map[ FromDigits, Partition[ First[ RealDigits[ E, 10, 20*10^ n ] ], n, 1 ] ] + 1; Catch[ Map[ ( i++; If[ m[ [ # ] ] == 0, m[ [ # ] ] = 1; If[ ++cnt == 10^n, Throw[ i ] ] ]) &, p ] ] ];
Table[ f[ n ], {n, 0, 5} ]

Extensions

a(6)-a(8) from Michael S. Branicky, Oct 04 2023