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A189559 Least prime k such that x' = k has n solutions, where x' is the arithmetic derivative (A003415) of x. 3
2, 5, 31, 167, 151, 491, 983, 887, 311, 1151, 1559, 2111, 1031, 2711, 4391, 4271, 3671, 3191, 5351, 9551, 11471, 14759, 8951, 13751, 11831, 5591, 19991, 10391, 15791, 28031, 30071, 37511, 43151, 27191, 40031, 31391, 52631, 53231, 35591, 52391, 50951 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

It is much easier finding composite numbers having many solutions. See A189558. For odd numbers, see A189560.

REFERENCES

See A003415.

LINKS

Donovan Johnson, Table of n, a(n) for n = 0..200

FORMULA

a(n) is the least prime k such that A099302(k) = n.

CROSSREFS

Cf. A003415, A099302, A189558, A189560.

Sequence in context: A266478 A107389 A261750 * A077483 A119242 A068145

Adjacent sequences:  A189556 A189557 A189558 * A189560 A189561 A189562

KEYWORD

nonn

AUTHOR

T. D. Noe, Apr 24 2011

STATUS

approved

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Last modified July 12 13:21 EDT 2020. Contains 335663 sequences. (Running on oeis4.)