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A307474
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SanD-68 primes p: such that p+d is also prime and sum of digits A007953(p(p+d)) = d, with d = 68.
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2
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19961, 28211, 43541, 44111, 62861, 66821, 69941, 83621, 86561, 88721, 89261, 92111, 94781, 99191, 120671, 125261, 129461, 129959, 130211, 132173, 132611, 136709, 138071, 141209, 141371, 150959, 153191, 156071, 157211, 158009, 159521, 161459, 163673, 164231, 165161, 165311, 167261, 170111, 171401, 178571
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OFFSET
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1,1
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COMMENTS
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SanD-d primes exist only for d = 14 + 18*k, k = -1/2, 0, 1, 2, 3, ...
This is the sequence for k = 3. See cross-references for other k and related sequences, in particular the main entry A307479 with further references.
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LINKS
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EXAMPLE
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a(1) = 19961 = A307479(186) = A307480(3) is the smallest SanD-68 prime: 19961 and 19961 + 68 = 20029 both are prime, and the digit sum A007953(19961*20029) = 3+9+9+7+9+8+8+6+9 = 68.
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PROG
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(PARI) print_A307474(N=100, d=68)=forprime(p=2, , isprime(p+d)&&sumdigits(p*(p+d))==d&&!print1(p, ", ")&&!N--&&break)
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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