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A109181
a(n) = A003132(A052034(n)).
4
2, 13, 17, 37, 73, 2, 11, 11, 59, 59, 131, 83, 131, 163, 17, 89, 11, 19, 59, 19, 67, 43, 67, 139, 139, 17, 97, 41, 113, 53, 61, 101, 37, 53, 61, 101, 73, 109, 131, 67, 139, 107, 179, 149, 109, 137, 83, 163, 139, 131, 179, 163, 211, 11, 83, 11, 19, 83, 131, 11, 83, 47, 67, 103, 11, 19, 59, 47, 107, 43, 67, 107, 179, 47, 127, 167, 199, 131, 67, 163
OFFSET
1,1
COMMENTS
For the primes p see A052034.
FORMULA
a(n) = A003132(A052034(n)). - Zak Seidov, Dec 30 2013
EXAMPLE
q=13 is a term because 13 = 2^2 + 3^2 and merging digits 2 and 3 makes p=23, which is a prime.
MAPLE
a:=proc(n) local nn, L: nn:=convert(n, base, 10): L:=nops(nn): if isprime(n) = true and isprime(add(nn[j]^2, j=1..L))=true then add(nn[j]^2, j=1..L) else end if end proc: seq(a(n), n=1..1200); # Emeric Deutsch, Jan 08 2008
CROSSREFS
Sequence in context: A177964 A174050 A122487 * A175448 A067522 A128852
KEYWORD
base,nonn
AUTHOR
Zak Seidov, Jun 21 2005
EXTENSIONS
More terms from Emeric Deutsch and Alvin Hoover Belt, Jan 08 2008
STATUS
approved