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A084048
Integers m such that the base-10 digit concatenation 2//m//3//m//5//m...//prime(49)//m//prime(50) is prime.
0
96, 359, 546, 1422, 1644, 1980, 2241, 3458, 3606, 4530, 4629, 5018, 5090, 5114, 5166, 7007, 7389, 8534, 9123, 9717, 9771, 10065, 10343, 10355, 10514, 10596, 11307, 11361, 11531, 12401, 12759, 13707, 14810, 15185, 15290, 15614, 15728, 16038
OFFSET
1,1
COMMENTS
This is in the family of sequences fp(j,m)=prime(1)//m//prime(2)//m//prime(3)//...//m//prime(j), of which A032711 = fp(2,m) is a simplest type.
EXAMPLE
96 is in the sequence because fp(50,k)=2//k//3//k//5//k//7//k//11//k//13...//k//229 fp(50,96)=296396596...22796229 is prime.
fp(50,96) is prime number with 219 digits.
MATHEMATICA
Select[Range[16100], PrimeQ[FromDigits[Flatten[IntegerDigits/@ Riffle[ Prime[ Range[ 50]], #]]]]&] (* Harvey P. Dale, Jan 07 2021 *)
CROSSREFS
Sequence in context: A301459 A220540 A292345 * A167983 A248457 A051483
KEYWORD
easy,nonn,base
AUTHOR
Farideh Firoozbakht, Jun 19 2003
STATUS
approved