A152493 Numbers n such that the decimal expansion of 2^n+5^n contains no 0's (probably 58 is last term).

0, 1, 2, 3, 4, 5, 6, 7, 9, 10, 12, 16, 17, 18, 30, 37, 58

Offset

0,3

Links

Table of n, a(n) for n=0..16.

Example

{n,2^n+5^n}: {0,2}, {1,7}, {2,29}, {3,133}, {4,641}, {5,3157}, {6,15689}, {7,78253}, {9,1953637}, {10,9766649}, {12,244144721}, {16,152587956161}, {17,762939584197}, {18,3814697527769}, {30,931322574616552257449}, {37,72759576141834396472156597}, {58,34694469519536141888238777858214286477369}.

Mathematica

Do[p=2^n+5^n; If[FreeQ[IntegerDigits[p], 0], Print[{n, p}]]], {n, 0, 2000}]
Select[Range[10000], DigitCount[2^#+5^#, 10, 0]==0&] (* Harvey P. Dale, Oct 14 2011 *)

Crossrefs

Cf. A074600, A007496.

Sequence in context: A261040 A087950 A060527 * A229028 A079002 A119984

Adjacent sequences: A152490 A152491 A152492 * A152494 A152495 A152496

Keyword

base,nonn

Author

Zak Seidov, Oct 25 2009

Status

approved