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A034276
Smallest prime that generates a prime pyramid of height n.
3
11, 29, 2, 5, 41, 251, 43, 145577, 51941, 4372877, 26901631, 366636187, 15387286403, 218761753811, 3313980408469
OFFSET
1,1
COMMENTS
Let p be prime; look for the smallest prime in {1|p|1, 3|p|3, 7|p|7, 9|p|9}, where '|' stands for concatenation; repeat until no such prime can be found; then height(p) = number of rows in pyramid.
a(13) > 10^10. - Donovan Johnson, Aug 13 2010
EXAMPLE
Example for p=43: 43 3433 334333 93343339 3933433393 939334333939 39393343339393, stop; height(43)=7.
CROSSREFS
KEYWORD
nonn,nice,base,more
AUTHOR
Felice Russo, Jan 25 2000
EXTENSIONS
More terms from Naohiro Nomoto, Jul 14 2001
a(11)-a(12) from Donovan Johnson, Aug 13 2010
a(13) from Chai Wah Wu, Apr 10 2015
a(14)-a(15) from Giovanni Resta, May 15 2020
STATUS
approved