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A092768 See Comments line. 1
14, 19, 31, 39, 49, 57, 67, 83, 95, 109, 121, 129, 139, 155, 171, 185, 199, 211, 219, 235, 247, 263, 285, 303, 309, 319, 327, 337, 377, 399, 407, 419, 445, 459, 469, 483, 499, 515, 531, 545, 571, 585, 589, 597, 631, 657, 685, 687, 697, 713, 725, 751, 769, 783 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Start with prime numbers, their differences and the absolute values of their differences:

2,.3,.5,.7,.11,.13,.17,.19,.23,.29

..1..2..2..4...2...4...2...4...6

....1..0..2..2...2...2...2...2

and sum the triangles:

a(1)=..2,3,5. = 2+3+5+1+2+1 = 14

........1,2

.........1

a(2)=..3,5,7. = 3+5+7+2+2+0 = 19

........2,2

.........0

etc.

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..1000

MATHEMATICA

difs[n_]:=Total[Flatten[{n, Abs[Differences[n]], Abs[Differences[n, 2]]}]]; difs/@Partition[Prime[Range[60]], 3, 1] (* Harvey P. Dale, Dec 19 2011 *)

CROSSREFS

Sequence in context: A121235 A007629 A241199 * A144080 A006576 A083247

Adjacent sequences:  A092765 A092766 A092767 * A092769 A092770 A092771

KEYWORD

nonn,easy

AUTHOR

Jorge Coveiro (jorgecoveiro(AT)yahoo.com), Apr 14 2004

EXTENSIONS

More terms from Pab Ter (pabrlos(AT)yahoo.com), May 24 2004

STATUS

approved

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Last modified March 27 08:50 EDT 2017. Contains 284146 sequences.