|
Search: id:A090870
|
|
|
| A090870 |
|
a(n) is the smallest m such that d(m+k-1)=2k for k=1,...,n where d(t)= prime(t+1)-prime(t)(differences of consecutive primes in arithmetic progression). |
|
+0
1
|
| |
|
|
OFFSET
|
1,1
|
|
|
COMMENT
|
Is this sequence infinite ? a(9) is greater than 105000000.
|
|
FORMULA
|
a[n_] := (For[m=1, !Sum[(d[m+k-1]-2k)^2, {k, n}]==0, m++ ];m)
|
|
EXAMPLE
|
a(8)=6496152 because prime(6496152)=113575727 and 113575727,
113575729,113575733,113575739,113575747,113575757,
113575769,113575783&113575799 are nine consecutive
primes with differences respectively 2,4,6,8,10,12,14&16.
|
|
MATHEMATICA
|
a[n_] := (For[m=1, !Sum[(d[m+k-1]-2k)^2, {k, n}]==0, m++ ]; m); Do[Print[a[n]], {n, 8}]
|
|
CROSSREFS
|
Cf. A049232.
Sequence in context: A087358 A057736 A130309 this_sequence A088542 A075840 A096225
Adjacent sequences: A090867 A090868 A090869 this_sequence A090871 A090872 A090873
|
|
KEYWORD
|
more,nonn
|
|
AUTHOR
|
Farideh Firoozbakht (f.firoozbakht(AT)sci.ui.ac.ir), Dec 11 2003
|
|
|
Search completed in 0.002 seconds
|
