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A154783
Row sums of triangle in A154720.
4
1, 6, 9, 20, 15, 30, 35, 40, 63, 70, 55, 108, 65, 70, 135, 112, 119, 162, 95, 140, 231, 198, 161, 312, 225, 182, 351, 196, 203, 450, 217, 352, 429, 238, 385, 540, 407, 418, 585, 440, 369, 798, 387, 396, 945, 414, 423, 720, 441, 650, 969, 676, 583, 1026, 825, 840
OFFSET
1,2
COMMENTS
Also, row sums of triangle in A154722. - Omar E. Pol, Jan 16 2009
FORMULA
a(n) = A154784(n) + n.
MAPLE
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
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Omar E. Pol, Jan 15 2009
EXTENSIONS
Extended by R. J. Mathar, Jan 18 2009
STATUS
approved