A173420 Triangular numbers which are sums of 4 consecutive primes.

36, 120, 780, 1596, 1830, 10440, 12090, 20706, 22578, 23436, 34716, 75466, 101926, 107880, 115440, 154290, 191890, 207690, 231540, 261726, 271216, 310866, 313236, 319600, 384126, 408156, 512578, 558096, 653796, 768180, 824970, 936396, 1094460

Offset

1,1

Links

Chai Wah Wu, Table of n, a(n) for n = 1..10000

Mathematica

Select[Table[Prime[n]+Prime[n+1]+Prime[n+2]+Prime[n+3], {n, 2*8!}], IntegerQ[Sqrt[1+8# ]]&]
Select[Total/@Partition[Prime[Range[50000]], 4, 1], OddQ[Sqrt[1+8#]]&] (* Harvey P. Dale, May 29 2021 *)

Prog

(Magma) [ t: n in [1..25000] | IsSquare(8*t+1) where t is &+[NthPrime(n+s): s in [0..3]] ]; // Bruno Berselli, Apr 28 2011

Crossrefs

Cf. A000040, A000217, A111163, A167788.

Sequence in context: A165966 A307939 A254146 * A271736 A280886 A278022

Adjacent sequences: A173417 A173418 A173419 * A173421 A173422 A173423

Keyword

nonn

Author

Vladimir Joseph Stephan Orlovsky, Feb 18 2010

Status

approved