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A119890 Prime duet leaders: largest number of a prime duet. 4
11, 23, 41, 43, 61, 101, 113, 131, 151, 223, 241, 311, 313, 331, 401, 421, 601, 1013, 1031, 1033, 1051, 1103, 1123, 1213, 1231, 1301, 1303, 1321, 2003, 2111, 2113, 2131, 2203, 2221, 2311, 3011, 3121, 3301, 4001, 4003, 4021, 4111, 4201, 5011, 5101, 10103 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
A prime duet is a pair of two different prime numbers such that the second number is a 1-digit number which is the sum of the digits of the first number.
The terms of the sequence must be at least 2 digits in length, so {5,5} is not a prime duet. - Harvey P. Dale, May 07 2021
LINKS
David A. Corneth, Table of n, a(n) for n = 1..10000 (first 600 terms from Harvey P. Dale)
L. Stevens, Prime ensembles
David A. Corneth, PARI program
EXAMPLE
113 is in the sequence because it is the largest number of the prime duet (113,5)
MATHEMATICA
Select[Prime[Range[5, 1300]], IntegerLength[Total[IntegerDigits[#]]]==1&&PrimeQ[Total[IntegerDigits[#]]]&] (* Harvey P. Dale, May 07 2021 *)
PROG
(PARI) See PARI link \\ David A. Corneth, May 07 2021
CROSSREFS
Sequence in context: A019356 A046440 A232116 * A094376 A086524 A060915
KEYWORD
nonn,base
AUTHOR
Luc Stevens (lms022(AT)yahoo.com), May 27 2006
EXTENSIONS
Corrected by Harvey P. Dale, May 07 2021
STATUS
approved

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Last modified June 4 17:49 EDT 2024. Contains 373102 sequences. (Running on oeis4.)