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A073035 Take A000040, omit commas: 23571113171923..., select 2-digit primes seen when scanning from left. 0
23, 71, 11, 11, 13, 31, 17, 71, 19, 23, 29, 31, 13, 37, 41, 43, 47, 53, 59, 61, 67, 71, 17, 73, 37, 79, 83, 89, 97, 71, 11, 3, 31, 7, 71, 11, 13, 31, 71, 13, 31, 11, 13, 37, 71, 13, 11, 71, 31, 67, 71, 17, 73, 31, 17, 79, 11, 19, 11, 19, 31, 19, 97, 71, 19, 11, 23, 29, 23, 23 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
The sequence allows leading zeroes, so for example 03 = 3 is treated as a valid two-digit prime. - Harvey P. Dale, May 06 2023
LINKS
EXAMPLE
In the sequence 2357111317192329... (primes without delimiters) two-digit primes are 23, 71, 11, 11, 13, 31, 17,
MATHEMATICA
p200=Flatten[IntegerDigits[Prime[Range[200]]]]; n=2; (* n-digit primes!*) pn=Partition[p200, n, 1]; ln=Length[pn]; tab=Table[Sum[10^(n-k)*pn[[i, k]], {k, n}], {i, ln}]; Select[tab, PrimeQ]
Module[{nn=100, prs}, prs=Flatten[IntegerDigits/@Prime[Range[nn]]]; Select[FromDigits/@ Partition[prs, 2, 1], PrimeQ]] (* Harvey P. Dale, May 06 2023 *)
CROSSREFS
Sequence in context: A042038 A116333 A042040 * A086104 A274050 A274675
KEYWORD
easy,nonn,base
AUTHOR
Zak Seidov, Aug 22 2002
STATUS
approved

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Last modified June 15 19:43 EDT 2024. Contains 373410 sequences. (Running on oeis4.)