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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

Cf. A119889, A119891, A119892.

Sequence in context: A019356 A046440 A232116 * A094376 A086524 A060915

Adjacent sequences: A119887 A119888 A119889 * A119891 A119892 A119893

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 February 1 03:56 EST 2023. Contains 359981 sequences. (Running on oeis4.)