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A287307 Primes that can be generated by the concatenation in base 6, in descending order, of two consecutive integers read in base 10. 0
13, 41, 443, 739, 887, 1109, 9547, 11717, 14321, 16057, 17359, 18661, 19963, 22133, 22567, 23869, 25171, 28643, 29077, 31247, 32983, 33851, 35153, 40361, 43399, 44267, 44701, 45569, 287933, 290527, 303497, 306091, 311279, 319061, 337219, 345001, 389099, 391693 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..38.

EXAMPLE

1 and 2 in base 6 are 1 and 2 and concat(2,1) = 21 in base 10 is 13;

5 and 6 in base 6 are 5 and 10 and concat(10,5) = 105 in base 10 is 41.

MAPLE

with(numtheory): P:= proc(q, h) local a, b, c, d, k, n; a:=convert(q+1, base, h); b:=convert(q, base, h); c:=[op(a), op(b)]; d:=0; for k from nops(c) by -1 to 1 do d:=h*d+c[k]; od; if isprime(d) then d; fi; end: seq(P(i, 6), i=0..1000);

MATHEMATICA

With[{b = 6}, Select[Map[FromDigits[Flatten@ IntegerDigits[#, b], b] &, Reverse /@ Partition[Range[0, 302], 2, 1]], PrimeQ]] (* Michael De Vlieger, May 23 2017 *)

CROSSREFS

Cf. A000040, A052089.

Sequence in context: A146995 A102130 A080186 * A201121 A116153 A116209

Adjacent sequences:  A287304 A287305 A287306 * A287308 A287309 A287310

KEYWORD

nonn,base,easy

AUTHOR

Paolo P. Lava, May 23 2017

STATUS

approved

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Last modified October 21 16:25 EDT 2019. Contains 328302 sequences. (Running on oeis4.)