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A083175 Row sums in A083175. 4
2, 12, 30, 84, 165, 312, 476, 760, 1035, 1740, 2046, 3108, 3731, 4816, 5640, 7632, 9027, 10980, 12730, 15620, 16863, 20856, 22908, 27768, 31525, 36764, 38934, 44940, 47415, 54240, 62992, 71264, 76857, 85068, 93870, 103284, 110371, 123880, 130260 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

If p is a prime then a(p) = prime(p)*T(p), where T(p) = the p-th triangular number.

PROG

(PARI) for(i=1, 120, p=prime(i); s=p*((i-1)*(i))/2; t=sum(k=1, i-1, p*k); k=i; while(denominator((s+k*p)/i)>1, k++); t+=k*p; print1(t, ", ")) (Herrgesell)

CROSSREFS

Cf. A083173, A083174, A083176.

Sequence in context: A002939 A118239 A127118 * A019258 A124903 A197954

Adjacent sequences:  A083172 A083173 A083174 * A083176 A083177 A083178

KEYWORD

nonn

AUTHOR

Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Apr 26 2003

EXTENSIONS

More terms from Lambert Herrgesell (zero815(AT)googlemail.com), Dec 30 2005

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Last modified February 16 11:30 EST 2012. Contains 205907 sequences.