A154783 - OEIS

A154783

Row sums of triangle in A154720.

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

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

OFFSET

1,2

COMMENTS

Also, row sums of triangle in A154722. - Omar E. Pol, Jan 16 2009

LINKS

Table of n, a(n) for n=1..56.

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

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

Sequence in context: A103186 A011988 A161782 * A096546 A376472 A357840

Adjacent sequences: A154780 A154781 A154782 * A154784 A154785 A154786

KEYWORD

easy,nonn

AUTHOR

Omar E. Pol, Jan 15 2009

EXTENSIONS

Extended by R. J. Mathar, Jan 18 2009

STATUS

approved