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A217049 With r and s successive primes, the smallest prime p that with its successor q first gives all prime counts of the ten base-10 digits for the value (p^r)*(q^s). 1
18329, 1913, 1063, 109, 932839, 85061, 29729989, 5653759, 1958731, 20891539, 35008723, 28265837, 2, 3, 6238777, 276624683, 92343187, 24205651, 49598321, 17722981, 46741657, 219329923 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Motivation for this sequence stems from the coincidence that (2^41)*(3^43) and (3^43)*(5^47) give prime counts for their digits.

LINKS

Table of n, a(n) for n=1..22.

EXAMPLE

(18329^2)*(18341^3) has each digit counted a prime number of times, and replacing the pair (18329,18341) with a smaller pair fails this criterion.

CROSSREFS

Cf. A216854.

Sequence in context: A237737 A145822 A286035 * A251025 A203783 A071368

Adjacent sequences:  A217046 A217047 A217048 * A217050 A217051 A217052

KEYWORD

nonn,base

AUTHOR

James G. Merickel, Sep 25 2012

STATUS

approved

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Last modified December 15 00:30 EST 2019. Contains 329988 sequences. (Running on oeis4.)