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A089348 Primes of the form smallest multiple of n followed by a 1. 2
11, 41, 31, 41, 101, 61, 71, 241, 181, 101, 331, 241, 131, 281, 151, 641, 1021, 181, 191, 401, 211, 661, 461, 241, 251, 521, 271, 281, 1451, 601, 311, 641, 331, 1021, 701, 1801, 1481, 761, 1171, 401, 821, 421, 431, 881, 1801, 461, 941, 3361, 491, 3001, 1021, 521 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Conjecture: {(a(n)-1)}/{10n} < n, or a(n) < 10*n^2 + 1.

The conjecture holds for 2 < n < 10^8. Heuristically, the chance of it failing for larger n is about 10^-300000 based on the integral of exp(-2.5*x/log(x)^2) using the Poisson model for numbers coprime to 10. [From Charles R Greathouse IV, Feb 15 2011]

LINKS

Table of n, a(n) for n=1..52.

CROSSREFS

Cf. A089533, A089534.

Sequence in context: A089776 A073626 A065144 * A088622 A121171 A239790

Adjacent sequences:  A089345 A089346 A089347 * A089349 A089350 A089351

KEYWORD

base,easy,nonn

AUTHOR

Amarnath Murthy, Nov 05 2003

EXTENSIONS

More terms from Ray Chandler, Nov 07 2003

STATUS

approved

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Last modified May 31 07:14 EDT 2020. Contains 334747 sequences. (Running on oeis4.)