A274698 - OEIS

A274698

a(n)=prime(n)-(2*last digit of prime(n)).

-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

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

LINKS

Table of n, a(n) for n=1..55.

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

Adjacent sequences: A274695 A274696 A274697 * A274699 A274700 A274701

KEYWORD

sign,base,less

AUTHOR

Dimitris Valianatos, Jul 02 2016

STATUS

approved