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A274698
a(n)=prime(n)-(2*last digit of prime(n)).
0
-2, -3, -5, -7, 9, 7, 3, 1, 17, 11, 29, 23, 39, 37, 33, 47, 41, 59, 53, 69, 67, 61, 77, 71, 83, 99, 97, 93, 91, 107, 113, 129, 123, 121, 131, 149, 143, 157, 153, 167, 161, 179, 189, 187, 183, 181, 209, 217, 213, 211, 227, 221, 239, 249, 243
OFFSET
1,1
EXAMPLE
For n=9, prime(9)=23. Last digit of 23 is 3, 23-2*3 = 17. So a(9) = 17.
PROG
(PARI) {
forprime(n=1, 300,
p=floor(n/10)*10;
d=n-p;
pd=p-d;
print1(pd", ")
)
}
CROSSREFS
Sequence in context: A284173 A276227 A355269 * A139790 A118784 A193889
KEYWORD
sign,base,less
AUTHOR
Dimitris Valianatos, Jul 02 2016
STATUS
approved