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A167608
Digit sum of cousin prime pairs.
1
10, 9, 12, 15, 15, 18, 21, 27, 18, 12, 15, 15, 24, 30, 18, 21, 27, 15, 18, 27, 33, 24, 27, 27, 30, 33, 30, 24, 30, 36, 33, 33, 39, 30, 36, 39, 39, 42, 27, 33, 39, 15, 27, 30, 18, 33, 24, 18, 24, 27, 27, 36, 39, 33, 33, 39, 30, 27, 36, 42, 42, 39, 42, 48, 33, 30, 21, 18, 27, 33, 36, 27, 33, 39, 27, 36, 33, 27, 39
OFFSET
1,1
COMMENTS
Except for the first term, all the others are multiples of 3.
LINKS
Eric Weisstein's World of Mathematics, Cousin Primes
EXAMPLE
The digit sum of the cousin prime pairs 223 and 227 is: 2+2+3+2+2+7 = 18.
MATHEMATICA
cptot[n_]:=Total[Join[IntegerDigits[n], IntegerDigits[n+4]]]; cptot/@Select[ Prime[Range[500]], PrimeQ[#+4]&] (* Harvey P. Dale, Apr 27 2014 *)
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Parthasarathy Nambi, Nov 07 2009
STATUS
approved