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Row sums of triangle in A154720.
4

%I #9 Jan 07 2019 04:20:47

%S 1,6,9,20,15,30,35,40,63,70,55,108,65,70,135,112,119,162,95,140,231,

%T 198,161,312,225,182,351,196,203,450,217,352,429,238,385,540,407,418,

%U 585,440,369,798,387,396,945,414,423,720,441,650,969,676,583,1026,825,840

%N Row sums of triangle in A154720.

%C Also, row sums of triangle in A154722. - _Omar E. Pol_, Jan 16 2009

%F a(n) = A154784(n) + n.

%p isA008578 := proc(n) RETURN(n=1 or isprime(n)) ; end: A154783 := proc(n) local a,d; a := n ; for d from 1 to n-1 do if isA008578(n-d) and isA008578(n+d) then a := a+2*n; fi; od: a ; end: for n from 1 to 80 do printf("%d,",A154783(n)) ; od: # _R. J. Mathar_, Jan 18 2009

%Y Cf. A154720, A154721, A154722, A154784, A154785, A154786.

%K easy,nonn

%O 1,2

%A _Omar E. Pol_, Jan 15 2009

%E Extended by _R. J. Mathar_, Jan 18 2009