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A089298 Smallest prime with digit product 10^n. 5
11, 251, 14551, 155581, 4545551, 45555581, 555555881, 44555555581, 455555558581, 5555555888551, 255555555585881, 14555555558558851, 155555555858885551, 2555555555558885851, 45555555555585855881 (list; graph; refs; listen; history; internal format)
OFFSET

0,1

COMMENTS

These numbers may not contain the digits {0, 3, 6, 7 or 9} and must end with the digit 1. Also the number of 2's plus half the number of 4's plus a quarter of the number of 8's must equal the number of 5's which in turn must equal n. - Robert G. Wilson v Nov 06 2003.

EXAMPLE

a(4) = 4545551 and the digit product = 10^4.

MATHEMATICA

NextPrim[n_] := Block[{k = n + 1}, While[ !PrimeQ[k], k++ ]; k]; a = Table[0, {10}]; p = 2; Do[ q = Log[10, Times @@ IntegerDigits[p]]; If[q != 0 && IntegerQ[q] && a[[q]] == 0, a[[q]] = p; Print[q, " = ", p]]; p = NextPrim[p], {n, 1, 10^9}]; a

CROSSREFS

Cf. A089365, A088653, A090840, A091465, A090841.

Sequence in context: A098672 A056210 A190680 * A012154 A009055 A009067

Adjacent sequences:  A089295 A089296 A089297 * A089299 A089300 A089301

KEYWORD

base,nonn

AUTHOR

Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Oct 30 2003

EXTENSIONS

Edited, corrected and extended Robert G. Wilson v (rgwv(AT)rgwv.com), Nov 06 2003

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Last modified February 17 11:18 EST 2012. Contains 206011 sequences.