A154785 Row sums of triangle in A154724.

1, 2, 3, 12, 15, 18, 21, 40, 45, 50, 55, 84, 65, 70, 105, 80, 119, 162, 57, 140, 189, 154, 161, 264, 225, 182, 297, 196, 203, 390, 155, 352, 429, 170, 385, 468, 333, 418, 585, 360, 369, 714, 387, 396, 855, 414, 423, 720, 343, 650

Offset: 1

Author

Omar E. Pol, Jan 15 2009

Keywords

• easy
• nonn

Comments

Also, row sums of triangle in A154726.

Links

• Nathaniel Johnston, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A154724, A154725, A154726, A154727, A154783, A154784, A154786.

Programs

Maple

for n from 1 to 50 do rsum:=0: for k from 1 to 2*n-1 do if(k=n or (isprime(k) and isprime(2*n-k)))then rsum:=rsum+k:fi:od: printf("%d, ",rsum):od: # Nathaniel Johnston, Apr 19 2011

Formula

a(n) = A154786(n) + n.

Extensions

a(11)-a(50) from Nathaniel Johnston, Apr 19 2011