Maheswara Rao Valluri has authored 3 sequences.
A305739
a(n) = n!*T(n) - 1, where T(n) is the n-th triangular number.
Original entry on oeis.org
0, 5, 35, 239, 1799, 15119, 141119, 1451519, 16329599, 199583999, 2634508799, 37362124799, 566658892799, 9153720575999, 156920924159999, 2845499424767999, 54420176498687999, 1094805903679487999, 23112569077678079999, 510909421717094399999
Offset: 1
See
A305738 for the indices of primes in this sequence.
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seq(n*(n+1)!/2-1,n=1..21);
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a(n) = n*(n+1)!/2 - 1; \\ Michel Marcus, Jun 23 2018
A305738
Numbers k such that k!*T(k) - 1 is prime, where T(k) is the k-th triangular number.
Original entry on oeis.org
2, 4, 28, 34, 47, 62, 228, 256, 258, 341, 848, 1362, 1709, 2262, 2692, 7907, 10396, 10501
Offset: 1
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Do[If[ PrimeQ[n(n +1)!/2 - 1], Print@ n], {n, 3000}]
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isok(n) = ispseudoprime(n(n+1)!/ 2 - 1);
A302859
Primes of the form (k+1)!*k/2 + 1.
Original entry on oeis.org
2, 7, 37, 241, 1801, 15121, 141121, 1451521, 16329601, 199584001, 37362124801, 566658892801, 9153720576001, 23112569077678080001, 186134520519971831808000001
Offset: 1
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Reap[For[k = 1, k <= 1000, k++, If[PrimeQ[p = (k+1)! k/2 + 1], Print["k = ", k, " p = ", p]; Sow[p]]]][[2, 1]]
This sequence was originally submitted as
A302174, then withdrawn, then reinstated with a new A-number by
N. J. A. Sloane, Apr 14 2018
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