A130758 - OEIS

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A130758

a(n) = n if n is not an odd prime number. Otherwise, a(n) = k, where k is the smallest integer such that n < 10^k.

0, 1, 2, 1, 4, 1, 6, 1, 8, 9, 10, 2, 12, 2, 14, 15, 16, 2, 18, 2, 20, 21, 22, 2, 24, 25, 26, 27, 28, 2, 30, 2, 32, 33, 34, 35, 36, 2, 38, 39, 40, 2, 42, 2, 44, 45, 46, 2, 48, 49, 50, 51, 52, 2, 54, 55, 56, 57, 58, 2, 60, 2, 62, 63, 64, 65, 66, 2, 68

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OFFSET

1,3

LINKS

Table of n, a(n) for n=1..69.

MATHEMATICA

Table[If[OddQ[n]&&PrimeQ[n], IntegerLength[n], n], {n, 0, 70}] (* Harvey P. Dale, Apr 13 2016 *)

CROSSREFS

Cf. A000027, A001477, A006005, A131516.

Sequence in context: A137374 A131516 A088140 * A130892 A353318 A239871

Adjacent sequences: A130755 A130756 A130757 * A130759 A130760 A130761

KEYWORD

nonn

AUTHOR

Mohammad K. Azarian, Aug 17 2007

EXTENSIONS

Offset corrected by Mohammad K. Azarian, Nov 19 2008

STATUS

approved