login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A173420 Triangular numbers which are sums of 4 consecutive primes. 3
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 (list; graph; refs; listen; history; text; internal format)
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

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified July 29 05:59 EDT 2021. Contains 346340 sequences. (Running on oeis4.)