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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; text; 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 LINKS 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: A056210 A182350 A190680 * A274129 A012154 A009055 Adjacent sequences:  A089295 A089296 A089297 * A089299 A089300 A089301 KEYWORD base,nonn AUTHOR Amarnath Murthy, Oct 30 2003 EXTENSIONS Edited, corrected and extended by Robert G. Wilson v, Nov 06 2003 STATUS approved

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Last modified December 15 04:23 EST 2019. Contains 329991 sequences. (Running on oeis4.)