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A153224
Numbers k such that the string k is found at position k-5 in the decimal digits of Pi.
2
26, 32, 41, 86, 2799, 469113068
OFFSET
1,1
EXAMPLE
a(1) = 26 because 26 occurs at offset (26-5) after the decimal in the digits of Pi.
PROG
(Python)
from sympy import S
# download https://stuff.mit.edu/afs/sipb/contrib/pi/pi-billion.txt, then
#with open('pi-billion.txt', 'r') as f: pi_digits = f.readline()
pi_digits = str(S.Pi.n(3*10**5+2))[:-2] # alternative to above
pi_digits = pi_digits.replace(".", "")
def afind():
for k in range(6, len(pi_digits)):
sk = str(k)
if sk == pi_digits[k-5:k-5+len(sk)]:
print(k, end=", ")
afind() # Michael S. Branicky, Jan 30 2022
CROSSREFS
KEYWORD
base,more,nonn
AUTHOR
Gil Broussard, Dec 21 2008
EXTENSIONS
a(6) from Michael S. Branicky, Jan 30 2022
STATUS
approved