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%I #13 Aug 03 2022 02:34:26
%S 11,13,17,19,23,29,31,37,41,43,47,53,59,61,67,71,73,79,83,89,97,4567,
%T 76543,23456789,1111111111111111111,11111111111111111111111
%N Straight-line primes.
%C Prime numbers with 2 digits together with the primes whose digits are in arithmetic progression. The structure of digits represents a straight line.
%C Note that in the graphic representation the points are connected by imaginary line segments (see also A135643).
%C Note that all two-digit primes are straight-line primes but this sequence has no three-digit terms.
%C No further terms between 23456789 and 115507867=prime(6600000). - _R. J. Mathar_, Dec 04 2009
%C All terms after 23456789 are repunit primes (A004022) with number of digits: 19, 23, 317, 1031, 49081, 86453, 109297, 270343, ... (A004023). - _Jens Kruse Andersen_, Jul 21 2014
%e The number 4567 is straight-line prime:
%e . . . .
%e . . . .
%e . . . 7
%e . . 6 .
%e . 5 . .
%e 4 . . .
%e . . . .
%e . . . .
%e . . . .
%e . . . .
%Y Cf. A000040, A004022, A004023, A134811, A134951, A134971, A135643, A167841, A167842, A167843, A167844, A167845, A167846, A167853.
%K base,nonn
%O 1,1
%A _Omar E. Pol_, Nov 14 2009
%E 2 more terms from _R. J. Mathar_, Dec 04 2009
%E a(25)-a(26) from _Jens Kruse Andersen_, Jul 21 2014
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