A129081 Primes appearing in partial sums of A030433 (primes ending in 9).

19, 107, 523, 1279, 1787, 4091, 16103, 18041, 46889, 68437, 104561, 155443, 161641, 174367, 187573, 303473, 330587, 359231, 419929, 430517, 634793, 878939, 974507, 1469753, 1510319, 1700851, 1902653, 2836961, 2982841, 3476299, 3807589

Offset: 1

Author

Tomas Xordan, May 11 2007

Keywords

• easy
• base
• nonn

Examples

			a(5) = 1787 because 1787 = A030433(1) + A030433(2) + A030433(3) + A030433(4) + A030433(5) + A030433(6) + A030433(7) + A030433(8) + A030433(9) + A030433(10) + A030433(11) + A030433(12) + A030433(13) = 19 + 29 + 59 + 79 + 89 + 109 + 139 + 149 + 179 + 199 + 229 + 239 + 269; and 1787 is a prime number.
		

Links

• Muniru A Asiru, Table of n, a(n) for n = 1..3000

Crossrefs

Cf. A030433, A000040.

Programs

GAP

P:=Filtered(List([1..5*10^5],n->10*n+9),IsPrime);;
a:=Filtered(List([1..Length(P)],i->Sum([1..i],k->P[k])),IsPrime); # Muniru A Asiru, Apr 28 2018

Mathematica

With[{pr9s=Select[Prime[Range[3000]],Last[IntegerDigits[#]]==9&]}, Select[ Accumulate[ pr9s],PrimeQ]] (* Harvey P. Dale, Dec 31 2011 *)

PARI

{s=0; forprime(p=2, 17300, if(p%10==9, s+=p; if(isprime(s), print1(s, ","))))} /* Klaus Brockhaus, May 13 2007 */

Formula

a(n) = A030433(1)+A030433(2)+...+A030433(x); a is a prime number.

Extensions

Entries checked by Klaus Brockhaus, May 13 2007

Better description from Harvey P. Dale, Dec 31 2011