A137980 Numbers k such that k^0 + (k+1)^1 + (k+2)^2 + (k+3)^3 + (k+4)^4 + (k+5)^5 + (k+6)^6 + (k+7)^7 is a prime.

4, 24, 28, 90, 112, 232, 310, 346, 480, 492, 522, 564, 592, 648, 666, 690, 694, 766, 802, 856, 868, 900, 930, 960, 990, 1030, 1038, 1060, 1102, 1134, 1212, 1218, 1240, 1264, 1308, 1446, 1522, 1570, 1578, 1704, 1822, 1852, 1858, 1866, 1882, 1896, 1906, 1912, 1978, 1990

Offset: 1

Author

Vladimir Joseph Stephan Orlovsky, May 06 2008

Keywords

• nonn

Links

• Andrew Howroyd, Table of n, a(n) for n = 1..1000

Crossrefs

Cf. A137950, A138023, A138059, A138065, A138089, A138091.

Programs

Mathematica

a={};Do[If[PrimeQ[n^0+(n+1)^1+(n+2)^2+(n+3)^3+(n+4)^4+(n+5)^5+(n+6)^6+(n+7)^7],AppendTo[a,n]],{n,10^3}];a

PARI

is(n)={isprime(sum(k=0, 7, (n+k)^k))}
select(is, [1..2000]) \\ Andrew Howroyd, Feb 02 2020