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A256118 Nine-digit zeroless pandigital numbers that are concatenation of three 3-digit prime numbers in increasing order. 1
127463859, 127643859, 149257683, 149257863, 149263587, 149263857, 149563827, 149653827, 157463829, 157643829, 163457829, 163547829, 239461587, 239461857, 239587641, 239641857, 241367859, 241673859, 241769853, 241853967, 251389467 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
The sequence is finite with last term a(136) = 659743821.
LINKS
EXAMPLE
(127, 463, 859) is the least triple of 3-digit primes together using each of nine digits 1..9 exactly once. Hence a(1) = 127463859.
MATHEMATICA
fQ[n_] := Block[{d = DigitCount@ n}, And[Max@ d == 1, Last@ d == 0, Plus @@ d == 9, n == FromDigits@ Flatten[IntegerDigits /@ Select[FromDigits /@ Partition[IntegerDigits@ n, 3], PrimeQ]]]]; Select[FromDigits /@ DeleteDuplicates[Flatten /@ (Sort@ Partition[IntegerDigits@ #, 3] & /@ FromDigits /@ Permutations[Range@ 9])], fQ@ # &] (* Michael De Vlieger, Mar 15 2015 *)
pnioQ[n_]:=Module[{idn=Partition[n, 3], a, b, c}, {a, b, c}=FromDigits/@ idn; a<b<c && AllTrue[{a, b, c}, PrimeQ]]; FromDigits/@ Select[ Permutations[ Range[ 9]], pnioQ] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Oct 18 2016 *)
CROSSREFS
Cf. A050278, A115301 (3 primes unsorted).
Sequence in context: A344832 A334346 A115301 * A036341 A184648 A258262
KEYWORD
nonn,base,fini,full
AUTHOR
Zak Seidov, Mar 15 2015
STATUS
approved

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Last modified March 29 02:23 EDT 2024. Contains 371264 sequences. (Running on oeis4.)