A273382 Numbers x = concat(a,b) such that a^b begins with the digits of x.

7525, 7533, 251196, 264770, 304732, 1768696, 2605292, 2653884, 32554685, 46415894

Offset

1,1

Links

Table of n, a(n) for n=1..10.

Example

7525 is a member because 75^25 is equal to 752543...6875, i.e., its first digits are 7525.

Mathematica

beg[x_, y_, n_] := x > 0 && Log10[x]*y >= Log10[n] && Block[{u = FractionalPart@ Log10[n+1]}, FractionalPart@ Log10[n] <= FractionalPart[ Log10[x]*y] < If[u == 0, 1, u]]; ok[n_] := Block[{p=1}, While[(p *= 10) < n && ! beg[Floor[n/p], Mod[n, p], n]]; p < n]; Select[Range[10^6], ok]

Crossrefs

Cf. A266817, A266818, A273383.

Sequence in context: A258604 A093225 A090742 * A186938 A185749 A077096

Adjacent sequences: A273379 A273380 A273381 * A273383 A273384 A273385

Keyword

nonn,base,more

Author

Giovanni Resta, Jun 06 2016

Status

approved